Systems and methods of protecting wireless power receivers using multiple rectifiers and establishing in-band communications using multiple rectifiers

- ENERGOUS CORPORATION

A wireless-power receiver includes an antenna coupled to a rectifier, and a depletion-mode switch coupled to the rectifier. The depletion-mode switch can create an impedance mismatch or an impedance match between the rectifier and the antenna. While the depletion-mode switch is in a default-closed state, it creates an impedance mismatch between the rectifier and the antenna. A first amount of alternating current received by the antenna as radio frequency (RF) signals is reflected away from the rectifier's input due to the impedance mismatch. A second amount of the alternating current causes the depletion-mode switch to begin transitioning to an open state, creating an impedance match between the rectifier and the antenna. While the depletion-mode switch is in the open state, creating an impedance match between the rectifier and the antenna, alternating current received by the antenna flows through the rectifier's input to be converted into direct current.

Skip to: Description  ·  Claims  ·  References Cited  · Patent History  ·  Patent History
Description
RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application Ser. No. 62/907,234, filed Sep. 27, 2019, and to U.S. Provisional Application Ser. No. 62/903,675, filed Sep. 20, 2019. Each of these applications is hereby incorporated by reference.

TECHNICAL FIELD

The embodiments herein generally relate to antennas, software, and devices used in wireless power transmission systems and, more specifically, to systems and methods of receivers with rectifiers capable of being used for communicating, warning of power fluctuations, and protecting against power surges.

BACKGROUND

Conventional wireless power transmission systems, such as charging pads, utilize both RF signals and induction to generate a magnetic field that is used to charge a device. These charging pads (i.e., transmitters) have to communicate with receivers to ensure that the device to be charge is not damaged by an unexpected surge in power or a power loss. To overcome such issues, the current approach has been to add a wireless communication chip (e.g., a Bluetooth radio) to both the transmitter and the receiver, which allows the devices to communicate with each other. However, the addition on these communication chips can be costly, which increases the cost of the wireless power transmission systems. In addition, in electronic devices where space is at a premium, the wireless communication chips occupy valuable shape.

Furthermore, establishing a communication connection between the transmitter and the receiver takes time, which can slow the time to start sending power from the transmitter to a receiver. Such a result is undesirable, because the wireless transmission of power is intended to be less involved than plugging in a device into a power source.

SUMMARY

Accordingly, there is a need for wireless charging systems (e.g., radio frequency (RF) charging pads) that address the problems identified above. To this end, systems and methods are described herein that are capable of allowing receivers to communicate and prepare for changes in power without having a dedicated communication chip (e.g., a Bluetooth radio). In some embodiments, such system and methods use to two rectifiers to solve the identified problems. It is also understood that in a two rectifier embodiment, a first rectifier is used to convert RF power to useable direct current (DC) to charge an electronic device while a second rectifier is configured to receive a smaller portion of power than the first rectifier, whereby this smaller portion of power is not used to charge the electronic device.

Typically, outputs of rectifiers are coupled to capacitors capable of reducing ripple. These capacitors are sized to match the outputted direct current, and the larger the direct current, the larger the capacitor needs to be to reduce ripple. However, these capacitors delay the detection (by either not charging or discharging fast enough) in incoming power. As a result, a second smaller rectifier that receives a smaller portion of power is capable of detecting changes in power faster than the components coupled to the first (i.e., larger power handling) rectifier. And once the second (i.e. smaller power handling) rectifier detects the change in power, it can communicate with the components coupled to the output of the first rectifier, and warn them that a power change has occurred.

In another aspect, this two rectifier embodiment allows for the second rectifier to adjust the impedance of the receiver causing a portion of the received RF power to be reflected back to the wireless power transmitter. By adjusting this impedance, the wireless power receiver can communicate with the wireless power transmitter. In one example, the wireless power transmitter can modulate its impedance (e.g., through control of the second rectifier) to signal the wireless power transmitter that a reduction in power is required by the wireless power receiver, or simply that power is no longer required.

(A1) In some embodiments, the solution explained above can be implemented on a wireless power receiver that includes a wireless-power-receiving antenna configured to receive radio frequency (RF) power signals, and convert energy from the received RF signals into an alternating current. The wireless power receiver also includes a primary rectifier that is configured to: (i) receive a first portion of the alternating current, and (ii) rectify the first portion of the alternating current into primary direct current having a first power level, the primary direct current used to provide power or charge to an electronic device. The wireless power receiver also includes a secondary rectifier that is configured to: (i) receive a second portion of the alternating current, and (ii) rectify the second portion of the alternating current into a secondary direct current having a second power level. The second power level of the secondary direct current is less than the first power level of the primary direct current. While a first voltage associated with the primary direct current and a second voltage associated with the secondary direct current can be similar, the power levels (the first and second power levels above) differ because load resistances for the primary and secondary direct currents are different.

(A2) In some embodiments of A1, the second power level of the secondary direct current indicates whether the antenna is receiving RF signals from a wireless-power-transmitting device.

(A3) In some embodiments of A2, an RF coupler is coupled to the antenna, and the RF coupler includes distinct first and second outputs. Furthermore, the primary rectifier is coupled to the first output of the RF coupler and the secondary rectifier is coupled to the second output of the RF coupler.

(A4) In some embodiments of A3, at least one impedance matching network is positioned between and coupled to the first output of the RF coupler and the secondary rectifier, whereby the at least one matching network is configured to match an impedance of a source of the RF signals.

(A5) In some embodiments of A3, at least one impedance matching network is positioned between and coupled to an input of the RF coupler and the antenna, whereby the at least one matching network is configured to match an impedance of a source of the RF signals.

(A6) In some embodiments of A3, the wireless power receiver also includes (i) one or more additional electrical components that are used to deliver the primary direct current that is used to power or charge to the electronic device and (ii) a controller configured to: (a) detect that the second power level of the secondary direct current satisfies one or more power-detection thresholds that indicate that the antenna is receiving RF signals from a wireless-power-transmitting device and (b) in response to detecting that the second direct current satisfies the one or more power-detection thresholds, send a signal that causes each of the one or more additional electrical components to prepare for receiving the primary direct current.

(A7) In some embodiments of A6, the one or more power-detection thresholds are satisfied when a voltage of the secondary direct current is in a range of approximately 5 volts to 30 volts. In some circumstances, the range can be either broadened (e.g., to be 1 volts to 40 volts), or narrowed (e.g., to be 5 volts to 10 volts).

(A8) In some embodiments of A7, detecting that the second power level of the secondary direct current satisfies one or more power-detection thresholds is performed by comparing the second power level to a respective power-detection threshold of the one or more power-detection thresholds at a first measurement point, a second measurement point, or both the first and second measurement points.

(A9) In some embodiments of A8, the first measurement point is located before a voltage divider that is configured to step down the voltage of the secondary direct current, and the second measurement point is located after the voltage divider.

(A10) In some embodiments of A6, the second portion of the alternating current is approximately less than 1% of the alternating current. In some embodiments, having the alternating current less than 1% minimizes impact on overall RF to DC conversion efficiency.

(A11) In some embodiments of A6, the wireless power receiver also includes: (i) a first storage component and (ii) a second storage component having a lower storage capacity that is less than the first storage component. Furthermore, the first storage component is coupled to an output of the primary rectifier while the second storage component is coupled to an output of the secondary rectifier. Moreover, the second storage component, due to its lower storage capacity, is configured to discharge faster than the first storage component, whereby discharge of the second storage component indicates to the wireless power receiver that RF signals are no longer being received at the antenna.

(A12) In some embodiments of any of A1-A11, the secondary rectifier is composed of: (i) an input configured to receive the second portion of the alternating current, (ii) a first diode, and (iii) a second diode. The input of the secondary rectifier is coupled to: a cathode of a first diode, wherein an anode of the first diode is coupled to a ground; and an anode of a second diode, wherein a cathode of the second diode is coupled to an output of the secondary rectifier.

(A13) In some embodiments of any of A1-A12, the secondary rectifier is composed of: (i) an input configured to receive the second portion of the alternating current, (ii) a first diode-connected transistor, and (iii) a second diode-connected transistor. The input of the secondary rectifier is coupled to: (i) a first diode-connected transistor, wherein the first diode-connected transistor is connected to a ground; and (ii) a second diode-connected transistor, wherein the second diode-connected transistor is connected to an output of the secondary rectifier.

(A14) In some embodiments of any of A3-A13, the RF coupler is a directional coupler.

(A15) In some embodiments of any of A3-A13, the RF coupler is a capacitive coupler.

(A16) In some embodiments of any of A3-A13, the RF coupler is a resistive coupler.

(B1) In another aspect, a method of communication between a wireless power receiver to a wireless power transmitter is performed. In some embodiments, the method includes receiving, by an antenna of the wireless power receiver, radio frequency (RF) signals from the wireless power transmitter, whereby the wireless power receiver substantially matches an impedance of the wireless power transmitter. The method also includes, while receiving the RF signals from the wireless power transmitter: (i) determining whether a communication criterion is satisfied, and (ii) in accordance with a determination that the communication criterion is satisfied, introducing an impedance mismatch between the wireless power receiver and the wireless power transmitter that causes a portion of the RF signals to be reflected by the antenna as a modulated signal. The transmitter is configured to receive and interpret the modulated signal without using a separate communication radio.

(B2) In some embodiments of B1, introducing the impedance mismatch includes creating one or more impedance mismatches between the wireless power receiver and the wireless power transmitter interspersed with one or more impedance matches between the wireless power receiver and the wireless power transmitter forming the modulated signal.

(B3) In some embodiments of B2, the wireless power transmitter interprets the modulated signal as an instruction to cease sending the RF signals to the wireless power receiver.

(B4) In some embodiments of B2, the wireless power transmitter interprets the modulated signal as an instruction to adjust transmission characteristics of the RF signals to the wireless power receiver.

(B5) In some embodiments of any of B1-B4, the method further includes, after introducing the impedance mismatch and while continuing to receive the RF signals from the wireless power transmitter, matching the impedance between the wireless power receiver and the wireless power transmitter, which stops reflection of the portion of the RF signals by the antenna.

(B6) In some embodiments of any of B1-B5, the wireless power transmitter ceases to transmit the RF signals to the wireless power receiver in response to receiving the modulated signal.

(B7) In some embodiments of any of B1-B6, the wireless power receiver includes an auxiliary rectifier, coupled to the antenna that receives some of the RF signals. Furthermore, introducing the impedance mismatch between the wireless power receiver and the wireless power transmitter includes adjusting a load of the auxiliary rectifier.

(B8) In some embodiments of B7, the wireless power receiver includes an auxiliary matching network coupled to and positioned between the antenna and the auxiliary rectifier. Furthermore, adjusting the load of the auxiliary rectifier causes an impedance mismatch between the auxiliary matching network of the wireless power receiver and the wireless power transmitter, which results the portion of the RF signals being reflected by the antenna.

(B9) In some embodiments of B7, the wireless power receiver includes a switch coupled to a load-adjusting mechanism, and the load-adjusting mechanism is coupled to the auxiliary rectifier. Moreover, the toggling the switch, which causes a change within the load-adjusting mechanism that produces a change in the load of the receiver, which results in the impedance mismatch between the wireless power receiver and the wireless power transmitter.

(B10) In another aspect, a wireless power receiver (e.g., receiver 120, FIG. 3) is provided. In some embodiments, the wireless power receiver includes: an antenna, a rectifier coupled to the antenna, a switch coupled to the rectifier, the switch being configured to create an impedance mismatch or match before an input of the rectifier, one or more processors; and memory storing one or more programs, which when executed by the one or more processors cause the transmitter to perform the method described in any one of B1-B9.

(B11) In yet another aspect, a wireless power receiver is provided and the wireless power receiver (e.g., receiver 120, FIG. 3) includes means for performing the method described in any one of B1-B9.

(B12) In still another aspect, a non-transitory computer-readable storage medium is provided. The non-transitory computer-readable storage medium stores executable instructions that, when executed by the wireless power receiver with one or more processors/cores, cause the wireless power receiver to perform the method described in any one of B1-B9.

(C1) In yet another aspect, a method of power surge protection for a wireless power receiver is performed. In some embodiments, this method is performed at a wireless power receiver that includes: (i) an antenna, (ii) a rectifier coupled to the antenna, and (iii) a switch coupled to the rectifier, the switch configured to create an impedance mismatch or match before an input of the rectifier. Further, the method includes, while the switch is in a default-closed state that grounds the switch and creates an impedance mismatch before an input of the rectifier: (i) receiving, by the antenna of the wireless power receiver, radio frequency (RF) signals as an alternating current, whereby a first portion of the alternating current is reflected away from the input of the rectifier due to the impedance mismatch between the wireless power receiver and the wireless power transmitter, and a second portion of the alternating current flows through the switch and to ground, and (ii) while the switch is in an open state that creates an impedance match between the wireless power receiver and the wireless power transmitter at the input of the rectifier: the first portion of the alternating current flows through the input of the rectifier, allowing the first portion of the alternating current to be converted into direct current that is used to charge or power a wireless electronic device. Moreover, the second portion of the alternating current flows through the switch and to the input of the rectifier, allowing the second portion of the alternating current to be converted into direct current that is used to charge or power a wireless electronic device.

(C2) In some embodiments of C1, a negative voltage generator is placed to drive the switch. For example, the negative voltage generator may be placed before the switch to drive the switch.

(C3) In some embodiments of any of C1-C2, the switch transitions from the default-closed state to the open state gradually over a period of time, and during the period of time, a part of the first portion of the alternating current continues to be reflected away from the input of the rectifier.

(C4) In some embodiments of C3, the switch transitions from default-closed to open state by using a Gallium Nitride (GaN) switch or a depletion mode metal oxide semiconductor (MOS) switch.

(C5) In some embodiments of C3, the method also includes, dynamically adjusting the period of time based on a detected voltage of the alternating current.

(C6) In some embodiments of C5, dynamically adjusting includes reducing the period of time based on a determination that the detected voltage does not satisfy a defined threshold value.

(C7) In some embodiments of C5, dynamically adjusting includes increasing the period of time based on a determination that the detected voltage satisfies a defined threshold value.

(C8) In some embodiments of any of C1-C7, the switch has a voltage threshold that is met before it enters the open fully open.

(C9) In some embodiments of C8, the voltage threshold is zero volts.

(C10) In some embodiments of any of C1-C9, the method further includes, while the switch is in the open state, ceasing to receive the RF signals by the antenna of the wireless power receiver. Ceasing to receive the RF signals causes the switch to transition back to the default-closed state from the open state.

(C11) In some embodiments of any of C1-C10, the wireless power receiver includes a coupling mechanism that is coupled to the antenna, the coupling mechanism including a first output and a second output. The first output of the coupling mechanism is coupled to the rectifier and the second output of the coupling mechanism is coupled to the switch.

(C12) In some embodiments of C11, the coupling mechanism partitions the alternating current. Further, the coupling mechanism: (i) directs a first portion of the alternating current to the first output of the coupling mechanism and (ii) directs a second portion of the alternating current to the second output of the coupling mechanism.

(C13) In some embodiments of C1-C12, the switch is coupled to an output of the rectifier.

(C14) In some embodiments of C1-C12, wherein the wireless power receiver also includes a matching network having (i) an input coupled to the first output of the coupling mechanism and (ii) an output coupled to the rectifier.

(C15) In some embodiments of C14, the switch is coupled to the matching network and the rectifier.

(C16) In another aspect, a wireless power receiver (e.g., receiver 120, FIG. 3) is provided. In some embodiments, the wireless power receiver includes: an antenna, a rectifier coupled to the antenna, a switch coupled to the rectifier, the switch being configured to create an impedance mismatch or match before an input of the rectifier, one or more processors; and memory storing one or more programs, which when executed by the one or more processors cause the transmitter to perform the method described in any one of C1-C15.

(C17) In yet another aspect, a wireless power receiver is provided and the receiver (e.g., receiver 120, FIG. 3) includes means for performing the method described in any one of C1-C15.

(C18) In still another aspect, a non-transitory computer-readable storage medium is provided. The non-transitory computer-readable storage medium stores executable instructions that, when executed by the wireless power receiver with one or more processors/cores, cause the wireless power receiver to perform the method described in any one of C1-C15.

Note that the various embodiments described above can be combined with any other embodiments described herein. The features and advantages described in the specification are not all inclusive and, in particular, many additional features and advantages will be apparent to one of ordinary skill in the art in view of the drawings, specification, and claims. Moreover, it should be noted that the language used in the specification has been principally selected for readability and instructional purposes, and not intended to circumscribe or limit the inventive subject matter.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the present disclosure can be understood in greater detail, a more particular description may be had by reference to the features of various embodiments, some of which are illustrated in the appended drawings. The appended drawings, however, merely illustrate pertinent features of the present disclosure and are therefore not to be considered limiting, for the description may admit to other effective features.

FIG. 1A is a block diagram of an RF wireless power transmission system, in accordance with some embodiments.

FIG. 1B is another block diagram of an RF wireless power transmission system, in accordance with some embodiments.

FIG. 1C is a block diagram showing components of an example RF charging pad that includes an RF power transmitter integrated circuit and antenna zones, in accordance with some embodiments.

FIG. 1D is a block diagram showing components of an example RF charging pad that includes an RF power transmitter integrated circuit coupled to a switch, in accordance with some embodiments.

FIG. 2 is a block diagram showing components of an example RF transmitter, in accordance with some embodiments.

FIG. 3 is a block diagram showing components of an example RF receiver, in accordance with some embodiments.

FIG. 4A is a circuit schematic illustrating an example RF receiver with two rectifiers for detecting changes in received RF power, in accordance with some embodiments.

FIG. 4B is a circuit schematic illustrating points at which a coupling mechanism may be added to the circuit, in accordance with some embodiments.

FIG. 4C illustrates circuit schematics for exemplary coupling mechanisms, in accordance with some embodiments, in accordance with some embodiments.

FIG. 4D illustrates circuit schematics for exemplary rectifiers, in accordance with some embodiments, in accordance with some embodiments.

FIG. 4E illustrates a circuit schematics for detecting when RF power is no longer received at the antenna, in accordance with some embodiments.

FIG. 4F illustrates circuit schematics of simplified rectifiers, in accordance with some embodiments.

FIG. 5A depicts a circuit schematic illustrating a system for protecting sensitive electrical components from power surges, in accordance with some embodiments.

FIG. 5B depicts a circuit schematic illustrating points at which a coupling mechanism may be added to the circuit, in accordance with some embodiments.

FIG. 6A depicts a circuit schematic illustrating a receiver capable of communicating with a transmitter, in accordance with some embodiments.

FIG. 6B depicts a circuit schematic illustrating points at which a coupling mechanism may be added to the circuit, in accordance with some embodiments.

FIG. 6C illustrates is a circuit schematic illustrating exemplary components for adjusting the load of a rectifier to cause an impedance mismatch, in accordance with some embodiments.

FIG. 7 is a flow diagram showing a process of a receiver communicating with a transmitter, in accordance with some embodiments.

In accordance with common practice, the various features illustrated in the drawings may not be drawn to scale. Accordingly, the dimensions of the various features may be arbitrarily expanded or reduced for clarity. In addition, some of the drawings may not depict all of the components of a given system, method or device. Finally, like reference numerals may be used to denote like features throughout the specification and figures.

DESCRIPTION OF EMBODIMENTS

Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the various described embodiments. However, it will be apparent to one of ordinary skill in the art that the various described embodiments may be practiced without these specific details. In other instances, well-known methods, procedures, components, circuits, and networks have not been described in detail so as not to unnecessarily obscure aspects of the embodiments.

FIG. 1A is a block diagram of components of wireless power transmission environment 100, in accordance with some embodiments. Wireless power transmission environment 100 includes, for example, transmitters 102 (e.g., transmitters 102a, 102b . . . 102n) and one or more receivers 120 (e.g., receivers 120a, 120b . . . 120n). In some embodiments, each respective wireless power transmission environment 100 includes a number of receivers 120, each of which is associated with a respective electronic device 122. In some instances, the transmitter 102 is referred to herein as a “wireless-power-transmitting device” or a “wireless power transmitter.” Additionally, in some instances, the receiver 120 is referred to herein as a “wireless-power-receiving device” or a “wireless power receiver.”

An example transmitter 102 (e.g., transmitter 102a) includes, for example, one or more processor(s) 104, a memory 106, one or more antenna arrays 110, one or more communications components 112 (also referred to herein as a “wireless communications radio,” a “communications radio” or simply a “radio”), and/or one or more transmitter sensors 114. In some embodiments, these components are interconnected by way of a communications bus 107. References to these components of transmitters 102 cover embodiments in which one or more of these components (and combinations thereof) are included. The components are discussed in further detail below with reference to FIG. 2.

In some embodiments, a single processor 104 (e.g., processor 104 of transmitter 102a) executes software modules for controlling multiple transmitters 102 (e.g., transmitters 102b . . . 102n). In some embodiments, a single transmitter 102 (e.g., transmitter 102a) includes multiple processors 104, such as one or more transmitter processors (configured to, e.g., control transmission of signals 116 by antenna array 110), one or more communications component processors (configured to, e.g., control communications transmitted by communications component 112 and/or receive communications by way of communications component 112) and/or one or more sensor processors (configured to, e.g., control operation of transmitter sensor 114 and/or receive output from transmitter sensor 114).

The wireless power receiver 120 receives power transmission signals 116 and/or communication signals 118 transmitted by transmitters 102. In some embodiments, the receiver 120 includes one or more antennas 124 (e.g., an antenna array including multiple antenna elements), power converter 126, receiver sensor 128, and/or other components or circuitry (e.g., processor(s) 140, memory 142, and/or communication component(s) 144. In some embodiments, these components are interconnected by way of a communications bus 146. References to these components of receiver 120 cover embodiments in which one or more of these components (and combinations thereof) are included.

The receiver 120 converts energy from received signals 116 (also referred to herein as RF power transmission signals, or simply, RF signals, RF waves, power waves, or power transmission signals) into electrical energy to power and/or charge electronic device 122. For example, the receiver 120 uses the power converter 126 to convert energy derived from power waves 116 to alternating current (AC) electricity or direct current (DC) electricity to power and/or charge the electronic device 122. Non-limiting examples of the power converter 126 include rectifiers, rectifying circuits, voltage conditioners, among suitable circuitry and devices.

In some embodiments, the receiver 120 is a standalone device that is detachably coupled to one or more electronic devices 122. For example, the electronic device 122 has processor(s) 132 for controlling one or more functions of the electronic device 122, and the receiver 120 has processor(s) 140 for controlling one or more functions of the receiver 120.

In some embodiments, the receiver 120 is a component of the electronic device 122. For example, processors 132 control functions of the electronic device 122 and the receiver 120. In addition, in some embodiments, the receiver 120 includes one or more processors 140, which communicates with processors 132 of the electronic device 122.

In some embodiments, the electronic device 122 includes one or more processors 132, memory 134, one or more communication components 136, and/or one or more batteries 130. In some embodiments, these components are interconnected by way of a communications bus 138. In some embodiments, communications between electronic device 122 and receiver 120 occur via communications component(s) 136 and/or 144. In some embodiments, communications between the electronic device 122 and the receiver 120 occur via a wired connection between communications bus 138 and communications bus 146. In some embodiments, the electronic device 122 and the receiver 120 share a single communications bus.

In some embodiments, the receiver 120 receives one or more power waves 116 directly from the transmitter 102 (e.g., via one or more antennas 124). In some embodiments, the receiver 120 harvests power waves from one or more pockets of energy created by one or more power waves 116 transmitted by the transmitter 102. In some embodiments, the transmitter 102 is a near-field transmitter that transmits the one or more power waves 116 within a near-field distance (e.g., less than approximately six inches away from the transmitter 102). In other embodiments, the transmitter 102 is a far-field transmitter that transmits the one or more power waves 116 within a far-field distance (e.g., more than approximately six inches away from the transmitter 102).

After the power waves 116 are received and/or energy is harvested from them, circuitry (e.g., integrated circuits, amplifiers, rectifiers, and/or voltage conditioner) of the receiver 120 converts the energy of the power waves to usable power (i.e., electricity), which powers the electronic device 122 and/or is stored to battery 130 of the electronic device 122. In some embodiments, a rectifying circuit of the receiver 120 translates the electrical energy from AC to DC for use by the electronic device 122. In some embodiments, a voltage conditioning circuit increases or decreases the voltage of the electrical energy as required by the electronic device 122. In some embodiments, an electrical relay conveys electrical energy from the receiver 120 to the electronic device 122.

In some embodiments, the electronic device 122 obtains power from multiple transmitters 102 and/or using multiple receivers 120. In some embodiments, the wireless power transmission environment 100 includes a plurality of electronic devices 122, each having at least one respective receiver 120 that is used to harvest power waves from the transmitters 102 into power for charging the electronic devices 122.

In some embodiments, the one or more transmitters 102 adjust values of one or more characteristics (e.g., waveform characteristics, such as phase, gain, direction, amplitude, polarization, and/or frequency) of power waves 116. For example, a transmitter 102 selects a subset of one or more antenna elements of antenna array 110 to initiate transmission of power waves 116, cease transmission of power waves 116, and/or adjust values of one or more characteristics used to transmit power waves 116. In some embodiments, the one or more transmitters 102 adjust power waves 116 such that trajectories of power waves 116 converge at a predetermined location within a transmission field (e.g., a location or region in space), resulting in controlled constructive or destructive interference patterns. The transmitter 102 may adjust values of one or more characteristics for transmitting the power waves 116 to account for changes at the wireless power receiver that may negatively impact transmission of the power waves 116.

Note that, in some embodiments, the transmitter 102 utilizes beamforming techniques to wirelessly transfer power to a receiver 120, while in other embodiments, the transmitter 102 does not utilize beamforming techniques to wirelessly transfer power to a receiver 120 (e.g., in circumstances in which no beamforming techniques are used, the transmitter controller IC 160 discussed below might be designed without any circuitry to allow for use of beamforming techniques, or that circuitry may be present, but might be deactivated to eliminate any beamforming control capability).

In some embodiments, respective antenna arrays 110 of the one or more transmitters 102 may include a set of one or more antennas configured to transmit the power waves 116 into respective transmission fields of the one or more transmitters 102. Integrated circuits (FIG. 1C) of the respective transmitter 102, such as a controller circuit (e.g., a radio frequency integrated circuit (RFIC)) and/or waveform generator, may control the behavior of the antennas. For example, based on the information received from the receiver 120 by way of the communication signal 118, a controller circuit (e.g., processor 104 of the transmitter 102, FIG. 1A) may determine values of the waveform characteristics (e.g., amplitude, frequency, trajectory, direction, phase, polarization, among other characteristics) of power waves 116 that would effectively provide power to the receiver 120, and in turn, the electronic device 122. The controller circuit may also identify a subset of antennas from the antenna arrays 110 that would be effective in transmitting the power waves 116. In some embodiments, a waveform generator circuit (not shown in FIG. 1A) of the respective transmitter 102 coupled to the processor 104 may convert energy and generate the power waves 116 having the specific values for the waveform characteristics identified by the processor 104/controller circuit, and then provide the power waves to the antenna arrays 110 for transmission.

In some embodiments, the communications component 112 transmits communication signals 118 by way of a wired and/or wireless communication connection to the receiver 120. In some embodiments, the communications component 112 generates communication signals 118 used for triangulation of the receiver 120 (e.g., test signals). In some embodiments, the communication signals 118 are used to convey information between the transmitter 102 and receiver 120 for adjusting values of one or more waveform characteristics used to transmit the power waves 116 (e.g., convey amounts of power derived from RF test signals). In some embodiments, the communication signals 118 include information related to status, efficiency, user data, power consumption, billing, geo-location, and other types of information.

In some embodiments, the communications component 112 transmits communication signals 118 to the receiver 120 by way of the electronic device 122a. For example, the communications component 112 may convey information to the communications component 136 of the electronic device 122a, which the electronic device 122a may in turn convey to the receiver 120 (e.g., via bus 138).

In some embodiments, the communications component 112 includes a communications component antenna for communicating with the receiver 120 and/or other transmitters 102 (e.g., transmitters 102b through 102n). In some embodiments, these communication signals 118 are sent using a first channel (e.g., a first frequency band) that is independent and distinct from a second channel (e.g., a second frequency band distinct from the first frequency band) used for transmission of the power waves 116.

In some embodiments, the receiver 120 includes a receiver-side communications component 144 configured to communicate various types of data with one or more of the transmitters 102, through a respective communication signal 118 generated by the receiver-side communications component (in some embodiments, a respective communication signal 118 is referred to as an advertising signal). The data may include location indicators for the receiver 120 and/or electronic device 122, a power status of the device 122, status information for the receiver 120, status information for the electronic device 122, status information about the power waves 116, and/or status information for pockets of energy. In other words, the receiver 120 may provide data to the transmitter 102, by way of the communication signal 118, regarding the current operation of the system 100, including: information identifying a present location of the receiver 120 or the device 122, an amount of energy (i.e., usable power) received by the receiver 120, and an amount of power received and/or used by the electronic device 122, among other possible data points containing other types of information.

In some embodiments, the data contained within communication signals 118 is used by the electronic device 122, the receiver 120, and/or the transmitters 102 for determining adjustments to values of one or more waveform characteristics used by the antenna array 110 to transmit the power waves 116. Using a communication signal 118, the transmitter 102 communicates data that is used, e.g., to identify receivers 120 within a transmission field, identify electronic devices 122, determine safe and effective waveform characteristics for power waves, and/or hone the placement of pockets of energy. In some embodiments, the receiver 120 uses a communication signal 118 to communicate data for, e.g., alerting transmitters 102 that the receiver 120 has entered or is about to enter a transmission field(e.g., come within wireless-power-transmission range of a transmitter 102), provide information about the electronic device 122, provide user information that corresponds to the electronic device 122, indicate the effectiveness of received power waves 116, and/or provide updated characteristics or transmission parameters that the one or more transmitters 102 use to adjust transmission of the power waves 116.

In some embodiments, the receiver 120 does not include a distinct communications component 144. Rather, the receiver 120 is configured to reflect RF signals transmitted by the transmitter 102 at the one or more antennas 124 and, importantly, modulate the reflected RF signals to convey data (or a message) to transmitter 102. In such embodiments, the transmitter 102 may also lack a distinct communications component. Instead, the transmitter 102 may receive the reflected RF signals at the one or more antenna arrays 110, and the transmitter 102 may demodulate the reflected RF signals in order to interpret them. Reflecting RF signals by the receiver 120 is discussed in further detail below with reference to FIGS. 6A-6C.

In some embodiments, transmitter sensor 114 and/or receiver sensor 128 detect and/or identify conditions of the electronic device 122, the receiver 120, the transmitter 102, and/or a transmission field. In some embodiments, data generated by the transmitter sensor 114 and/or receiver sensor 128 is used by the transmitter 102 to determine appropriate adjustments to values of one or more waveform characteristics used to transmit the power waves 116. Data from transmitter sensor 114 and/or receiver sensor 128 received by the transmitter 102 includes, e.g., raw sensor data and/or sensor data processed by a processor 104, such as a sensor processor. Processed sensor data includes, e.g., determinations based upon sensor data output. In some embodiments, sensor data received from sensors that are external to the receiver 120 and the transmitters 102 is also used (such as thermal imaging data, information from optical sensors, and others).

FIG. 1B is another block diagram of an RF wireless power transmission system 150 in accordance with some embodiments. In some embodiments, the RF wireless power transmission system 150 includes a far-field transmitter (not shown). In some embodiments, the RF wireless power transmission system 150 includes a RF charging pad 151 (also referred to herein as a near-field (NF) charging pad 151 or RF charging pad 151). The RF charging pad 151 may be an example of the transmitter 102 in FIG. 1A.

In some embodiments, the RF charging pad 151 includes an RF power transmitter integrated circuit 160 (described in more detail below). In some embodiments, the RF charging pad 151 includes one or more optional communications components 112 (e.g., wireless communication components, such as WI-FI or BLUETOOTH radios). Alternatively, in some embodiments, the RF charging pad 151 does not include the optional communications components 112. In such embodiments, the RF charging pad 151 includes alternative means for communicating with other devices (e.g., the RF charging pad 151 receives and interprets RF signals reflected by a receiver 120). In some embodiments, the RF charging pad 151 also connects to one or more power amplifier units 108-1, . . . 108-n (PA or PA units) to control operation of the one or more power amplifier units when they drive external power-transfer elements (e.g., antennas 290). In some embodiments, RF power is controlled and modulated at the RF charging pad 151 via switch circuitry as to enable the RF wireless power transmission system to send RF power to one or more wireless receiving devices via the TX antenna array 110.

The optional communication component(s) 112 enable communication between the RF charging pad 151 and one or more communication networks, and are discussed in further detail above with reference to FIG. 1A. In some instances, the communication component(s) 112 are not able to communicate with wireless power receivers for various reasons, e.g., because there is no power available for the communication component(s) to use for the transmission of data signals or because the wireless power receiver 120 itself does not actually include any communication component of its own. As such, it is important to design near-field charging pads that are still able to uniquely identify different types of devices and, when a wireless power receiver is detected, figure out if that wireless power receiver is authorized to receive wireless power.

FIG. 1C is a block diagram of the RF power transmitter integrated circuit 160 (the “integrated circuit”) in accordance with some embodiments. In some embodiments, the integrated circuit 160 includes a CPU subsystem 170, an external device control interface, an RF subsection for DC to RF power conversion, and analog and digital control interfaces interconnected via an interconnection component, such as a bus or interconnection fabric block 171. In some embodiments, the CPU subsystem 170 includes a microprocessor unit (CPU) 202 with related Read-Only-Memory (ROM) 172 for device program booting via a digital control interface, e.g. an I2C port, to an external FLASH containing the CPU executable code to be loaded into the CPU Subsystem Random Access Memory (RAM) 174 (e.g., memory 206, FIG. 2A) or executed directly from FLASH. In some embodiments, the CPU subsystem 170 also includes an encryption module or block 176 to authenticate and secure communication exchanges with external devices, such as wireless power receivers that attempt to receive wirelessly delivered power from the RF charging pad 150.

In some embodiments, the RF IC 160 also includes (or is in communication with) a power amplifier controller IC 161A (PA IC) that is responsible for controlling and managing operations of a power amplifier (or multiple power amplifiers), including for reading measurements of impedance at various measurement points within the power amplifier 108, whereby these measurements are used, in some instances, for detecting of foreign objects. The PA IC 161A may be on the same integrated circuit at the RF IC 160, or may be on its on integrated circuit that is separate from (but still in communication with) the RF IC 160. Additional details regarding the architecture and operation of the PA IC are provided in U.S. Provisional Application No. 62/903,677, the disclosure of which is incorporated by reference herein in its entirety.

In some embodiments, executable instructions running on the CPU (such as those shown in the memory 106 in FIG. 2 and described below) are used to manage operation of the RF charging pad 151 and to control external devices through a control interface, e.g., SPI control interface 175, and the other analog and digital interfaces included in the RF power transmitter integrated circuit 160. In some embodiments, the CPU subsystem also manages operation of the RF subsection of the RF power transmitter integrated circuit 160, which includes an RF local oscillator (LO) 177 and an RF transmitter (TX) 178. In some embodiments, the RF LO 177 is adjusted based on instructions from the CPU subsystem 170 and is thereby set to different desired frequencies of operation, while the RF TX converts, amplifies, modulates the RF output as desired to generate a viable RF power level.

In the descriptions that follow, various references are made to antenna zones and power-transfer zones, which terms are used synonymously in this disclosure. In some embodiments the antenna/power-transfer zones may include antenna elements that transmit propagating radio frequency waves but, in other embodiments, the antenna/power transfer zones may instead include capacitive charging couplers that convey electrical signals but do not send propagating radio frequency waves.

In some embodiments, the RF power transmitter integrated circuit 160 provides the viable RF power level (e.g., via the RF TX 178) to an optional beamforming integrated circuit (IC) 109, which then provides phase-shifted signals to one or more power amplifiers 108. In some embodiments, the beamforming IC 109 is used to ensure that power transmission signals sent using two or more antennas 210 (e.g., each antenna 210 may be associated with a different antenna zone 290 or may each belong to a single antenna zone 290) to a particular wireless power receiver are transmitted with appropriate characteristics (e.g., phases) to ensure that power transmitted to the particular wireless power receiver is maximized (e.g., the power transmission signals arrive in phase at the particular wireless power receiver). In some embodiments, the beamforming IC 109 forms part of the RF power transmitter IC 160. In embodiments in which capacitive couplers (e.g., capacitive charging couplers 244) are used as the antennas 210, then optional beamforming IC 109 may not be included in the RF power transmitter integrated circuit 160.

In some embodiments, the RF power transmitter integrated circuit 160 provides the viable RF power level (e.g., via the RF TX 178) directly to the one or more power amplifiers 108 and does not use the beamforming IC 109 (or bypasses the beamforming IC if phase-shifting is not required, such as when only a single antenna 210 is used to transmit power transmission signals to a wireless power receiver). In some embodiments, the PA IC 161A receives the viable RF power level and provides that to the one or more power amplifiers 108.

In some embodiments, the one or more power amplifiers 108 then provide RF signals to the antenna zones 290 (also referred to herein as “power-transfer zones”) for transmission to wireless power receivers that are authorized to receive wirelessly delivered power from the RF charging pad 151. In some embodiments, each antenna zone 290 is coupled with a respective PA 108 (e.g., antenna zone 290-1 is coupled with PA 108-1 and antenna zone 290-N is coupled with PA 108-N). In some embodiments, multiple antenna zones are each coupled with a same set of PAs 108 (e.g., all PAs 108 are coupled with each antenna zone 290). Various arrangements and couplings of PAs 108 to antenna zones 290 allow the RF charging pad 151 to sequentially or selectively activate different antenna zones in order to determine the most efficient antenna zone 290 to use for transmitting wireless power to a wireless power receiver. In some embodiments, the one or more power amplifiers 108 are also in communication with the CPU subsystem 170 to allow the CPU 202 to measure output power provided by the PAs 108 to the antenna zones 110 of the RF charging pad 151.

FIG. 1C also shows that, in some embodiments, the antenna zones 290 of the RF charging pad 151 may include one or more antennas 210A-N. In some embodiments, each antenna zone of the plurality of antenna zones 290 includes one or more antennas 210 (e.g., antenna zone 290-1 includes one antenna 210-A and antenna zones 290-N includes multiple antennas 210). In some embodiments, a number of antennas included in each of the antenna zones is dynamically defined based on various parameters, such as a location of a wireless power receiver on the RF charging pad 151. In some embodiments, each antenna zone 290 may include antennas of different types, while in other embodiments each antenna zone 290 may include a single antenna of a same type, while in still other embodiments, the antennas zones may include some antenna zones that include a single antenna of a same type and some antenna zones that include antennas of different types. In some embodiments the antenna/power-transfer zones may also or alternatively include capacitive charging couplers that convey electrical signals but do not send propagating radio frequency waves.

In some embodiments, the RF charging pad 151 may also include a temperature monitoring circuit that is in communication with the CPU subsystem 170 to ensure that the RF charging pad 151 remains within an acceptable temperature range. For example, if a determination is made that the RF charging pad 151 has reached a threshold temperature, then operation of the RF charging pad 151 may be temporarily suspended until the RF charging pad 151 falls below the threshold temperature.

By including the components shown for RF power transmitter circuit 160 (FIG. 1C) on a single chip, such transmitter chips are able to manage operations at the transmitter chips more efficiently and quickly (and with lower latency), thereby helping to improve user satisfaction with the charging pads that are managed by these transmitter chips. For example, the RF power transmitter circuit 160 is cheaper to construct, has a smaller physical footprint, and is simpler to install.

FIG. 1D is a block diagram of a charging pad 294 in accordance with some embodiments. The charging pad 294 is an example of the charging pad 151 (FIG. 1B), however, one or more components included in the charging pad 151 are not included in the charging pad 294 for ease of discussion and illustration.

The charging pad 294 includes an RF power transmitter integrated circuit 160, one or more power amplifiers 108, a PA IC 161A (which may be on the same or a separate IC from the RF power transmitter IC 160), and a transmitter antenna array 290 having multiple antenna zones. Each of these components is described in detail above with reference to FIGS. 1A-1C. Additionally, the charging pad 294 includes a switch 295 (i.e., transmitter-side switch), positioned between the power amplifiers 108 and the antenna array 290, having a plurality of switches 297-A, 297-B, . . . 297-N. The switch 295 is configured to switchably connect one or more power amplifiers 108 with one or more antenna zones of the antenna array 290 in response to control signals provided by the RF power transmitter integrated circuit 160.

To accomplish the above, each switch 297 is coupled with (e.g., provides a signal pathway to) a different antenna zone of the antenna array 290. For example, switch 297-A may be coupled with a first antenna zone 290-1 (FIG. 1C) of the antenna array 290, switch 297-B may be coupled with a second antenna zone 290-2 of the antenna array 290, and so on. Each of the plurality of switches 297-A, 297-B, . . . 297-N, once closed, creates a unique pathway between a respective power amplifier 108 (or multiple power amplifiers 108) and a respective antenna zone of the antenna array 290. Each unique pathway through the switch 295 is used to selectively provide RF signals to specific antenna zones of the antenna array 290. It is noted that two or more of the plurality of switches 297-A, 297-B, . . . 297-N may be closed at the same time, thereby creating multiple unique pathways to the antenna array 290 that may be used simultaneously.

In some embodiments, the RF power transmitter integrated circuit 160 (or the PA IC 161A, or both) is (are) coupled to the switch 295 and is configured to control operation of the plurality of switches 297-A, 297-B, . . . 297-N (illustrated as a “control out” signal in FIGS. 1B and 1D). For example, the RF power transmitter integrated circuit 160 may close a first switch 297-A while keeping the other switches open. In another example, the RF power transmitter integrated circuit 160 may close a first switch 297-A and a second switch 297-B, and keep the other switches open (various other combinations and configuration are possible). Moreover, the RF power transmitter integrated circuit 160 is coupled to the one or more power amplifiers 108 and is configured to generate a suitable RF signal (e.g., the “RF Out” signal) and provide the RF signal to the one or more power amplifiers 108. The one or more power amplifiers 108, in turn, are configured to provide the RF signal to one or more antenna zones of the antenna array 290 via the switch 295, depending on which switches 297 in the switch 295 are closed by the RF power transmitter integrated circuit 160.

In some embodiments, the charging pad is configured to transmit test power transmission signals and/or regular power transmission signals using different antenna zones, e.g., depending on a location of a receiver on the charging pad. Accordingly, when a particular antenna zone is selected for transmitting test signals or regular power signals, a control signal is sent to the switch 295 from the RF power transmitter integrated circuit 160 to cause at least one switch 297 to close. In doing so, an RF signal from at least one power amplifier 108 can be provided to the particular antenna zone using a unique pathway created by the now-closed at least one switch 297.

In some embodiments, the switch 295 may be part of (e.g., internal to) the antenna array 290. Alternatively, in some embodiments, the switch 295 is separate from the antenna array 290 (e.g., the switch 295 may be a distinct component, or may be part of another component, such as the power amplifier(s) 108). It is noted that any switch design capable of accomplishing the above may be used, and the design of the switch 295 illustrated in FIG. 1D is merely one example.

FIG. 2 is a block diagram illustrating a representative transmitter device 102 (also sometimes referred to herein as a transmitter 102, a wireless power transmitter 102, and a wireless-power-transmitting device 102) in accordance with some embodiments. In some embodiments, the transmitter device 102 includes one or more processors 104 (e.g., CPUs, ASICs, FPGAs, microprocessors, and the like), one or more optional communication components 112 (e.g., radios), memory 106, one or more antennas 110, and one or more communication buses 108 for interconnecting these components (sometimes called a chipset). In some embodiments, the transmitter device 102 includes one or more sensors 114 as described above with reference to FIG. 1A. In some embodiments, the transmitter device 102 includes one or more output devices such as one or more indicator lights, a sound card, a speaker, a small display for displaying textual information and error codes, etc. In some embodiments, the transmitter device 102 includes a location detection device, such as a GPS (global positioning satellite) or other geo-location receiver, for determining the location of the transmitter device 102.

The communication components 112 enable communication between the transmitter 102 and the receiver 120 (e.g., one or more communication networks). In some embodiments, the communication components 112 include, e.g., hardware capable of data communications using any of a variety of wireless protocols (e.g., IEEE 802.15.4, Wi-Fi, ZigBee, 6LoWPAN, Thread, Z-Wave, Bluetooth Smart, ISA100.11a, WirelessHART, MiWi, etc.) wired protocols (e.g., Ethernet, HomePlug, etc.), and/or any other suitable communication protocol, including communication protocols not yet developed as of the filing date of this document.

The memory 106 includes high-speed random access memory, such as DRAM, SRAM, DDR SRAM, or other random access solid state memory devices; and, optionally, includes non-volatile memory, such as one or more magnetic disk storage devices, one or more optical disk storage devices, one or more flash memory devices, or one or more other non-volatile solid state storage devices. The memory 106, or alternatively the non-volatile memory within memory 106, includes a non-transitory computer-readable storage medium. In some embodiments, the memory 106, or the non-transitory computer-readable storage medium of the memory 106, stores the following programs, modules, and data structures, or a subset or superset thereof:

    • operating logic 216 including procedures for handling various basic system services and for performing hardware dependent tasks;
    • communication module 218 for coupling to and/or communicating with remote devices (e.g., remote sensors, transmitters, receivers, servers, etc.), in conjunction with communication component(s) 112 and/or antenna(s) 110;
    • sensor module 220 for obtaining and processing sensor data (e.g., in conjunction with sensor(s) 114) to, for example, determine the presence, velocity, and/or positioning of object in the vicinity of the transmitter 102;
    • optimal phase setting module 222 for determining an optimal phase antenna for respective antennas in the transmitter's antenna array 110. In some embodiments, as discussed below with reference to FIGS. 5A-5C, the optimal phase setting module 222 determines the optimal phase setting using either a binary search method or a least squares method, or some combination thereof;
    • power wave generating module 224 for generating and transmitting (e.g., in conjunction with antenna(s) 110) power waves. In some embodiments, the power wave generating module 224 is associated with (or includes) the optimal phase setting module 222 is used to determine the optimal phase; and
    • database 226, including but not limited to:
      • sensor information 228 for storing and managing data received, detected, and/or transmitted by one or more sensors (e.g., sensors 114 and/or one or more remote sensors);
      • test phases 230 for storing and managing predetermined test phases of test signals transmitted by the power wave generating module 224. In some embodiments, as discussed below with reference to FIGS. 5A-5C, the test phases are separated by a predetermined interval corresponding to known characteristics of a pure sinusoidal wave;
      • optimal phases 232 for storing and managing optimal antenna phases determined by the optimal phase setting module 222 for one or more antennas 110; and
      • communication protocol information 234 for storing and managing protocol information for one or more protocols (e.g., custom or standard wireless protocols, such as ZigBee, Z-Wave, etc., and/or custom or standard wired protocols, such as Ethernet).

Each of the above-identified elements (e.g., modules stored in memory 106 of the transmitter 102) is optionally stored in one or more of the previously mentioned memory devices, and corresponds to a set of instructions for performing the function(s) described above. The above identified modules or programs (e.g., sets of instructions) need not be implemented as separate software programs, procedures, or modules, and thus various subsets of these modules are optionally combined or otherwise rearranged in various embodiments. In some embodiments, the memory 106, optionally, stores a subset of the modules and data structures identified above. Furthermore, the memory 106, optionally, stores additional modules and data structures not described above, such as a tracking module for tracking the movement and positioning of objects within a transmission field.

FIG. 3 is a block diagram illustrating a representative receiver device 120 (also referred to herein as a receiver 120, a wireless power receiver 120, and a wireless-power-receiving device 120) in accordance with some embodiments. In some embodiments, the receiver device 120 includes one or more processors 140 (e.g., CPUs, ASICs, FPGAs, microprocessors, and the like), one or more optional communication components 144, memory 142, one or more antennas 124, power harvesting circuitry 310, and one or more communication buses 308 for interconnecting these components (sometimes called a chipset). In some embodiments, the receiver device 120 includes one or more sensors 128 such as one or sensors described above with reference to FIG. 1A. In some embodiments, the receiver device 120 includes an energy storage device 312 for storing energy harvested via the power harvesting circuitry 310. In various embodiments, the energy storage device 312 includes one or more batteries (e.g., battery 130, FIG. 1A), one or more capacitors, one or more inductors, and the like.

As described above with reference to FIG. 1A, in some embodiments, the receiver 120 is internally or externally connected to an electronic device (e.g., electronic device 122a, FIG. 1A) via a connection 138 (e.g., a bus). In some embodiments, the energy storage device 312 is part of the electronic device.

In some embodiments, the power harvesting circuitry 310 includes one or more rectifying circuits and/or one or more power converters. In some embodiments, the power harvesting circuitry 310 includes one or more components (e.g., a power converter 126) configured to convert energy from power waves and/or energy pockets to electrical energy (e.g., electricity). In some embodiments, the power harvesting circuitry 310 is further configured to supply power to a coupled electronic device (e.g., an electronic device 122), such as a laptop or phone. In some embodiments, supplying power to a coupled electronic device include translating electrical energy from an AC form to a DC form (e.g., usable by the electronic device 122).

The communication component(s) 144 enable communication between the receiver 120 and the transmitter 102 (e.g., via one or more communication networks). In some embodiments, the communication component(s) 144 include, e.g., hardware capable of data communications using any of a variety of custom or standard wireless protocols (e.g., IEEE 802.15.4, Wi-Fi, ZigBee, 6LoWPAN, Thread, Z-Wave, Bluetooth Smart, ISA100.11a, WirelessHART, MiWi, etc.) custom or standard wired protocols (e.g., Ethernet, HomePlug, etc.), and/or any other suitable communication protocol, including communication protocols not yet developed as of the filing date of this document. In some embodiments, the receiver 120 may utilize a built-in communication component (e.g., a Bluetooth radio) or an electronic device with which the receiver 120 is coupled, and therefore, in these embodiments, the receiver 120 may not include its own communication component. In some other embodiments, the receiver 120 does not include a distinct communication component 144. Rather, the receiver 120 may use an in-band communication technique to communicate with other devices, as explained below with reference to FIGS. 6A-6C and FIG. 7.

The memory 142 includes high-speed random access memory, such as DRAM, SRAM, DDR SRAM, or other random access solid state memory devices; and, optionally, includes non-volatile memory, such as one or more magnetic disk storage devices, one or more optical disk storage devices, one or more flash memory devices, or one or more other non-volatile solid state storage devices. The memory 142, or alternatively the non-volatile memory within memory 142, includes a non-transitory computer-readable storage medium. In some embodiments, the memory 142, or the non-transitory computer-readable storage medium of the memory 142, stores the following programs, modules, and data structures, or a subset or superset thereof:

    • operating logic 314 including procedures for handling various basic system services and for performing hardware dependent tasks;
    • communication module 316 for coupling to and/or communicating with remote devices (e.g., remote sensors, transmitters, other receivers, servers, electronic devices, mapping memories, etc.) in conjunction with the optional communication component(s) 144 and/or antenna(s) 124;
    • sensor module 318 for obtaining and processing sensor data (e.g., in conjunction with sensor(s) 128) to, for example, determine the presence, velocity, and/or positioning of the receiver 120, a transmitter 102, or an object in the vicinity of the receiver 120;
    • power receiving module 320 for receiving (e.g., in conjunction with antenna(s) 124 and/or power harvesting circuitry 310) and optionally converting (e.g., in conjunction with power harvesting circuitry 310) the energy (e.g., to direct current); transferring the energy to a coupled electronic device (e.g., an electronic device 122); and optionally storing the energy (e.g., in conjunction with energy storage device 312)
    • power determining module 321 for determining (in conjunction with operation of the power receiving module 320) an amount of power received by the receiver based on energy extracted from power waves (or RF test signals) and/or pockets or energy at which the power waves converge (e.g., RF signals 116, FIG. 1A). In some embodiments, as discussed below with reference to FIGS. 5A-5B, after determining an amount of power received by the receiver, the receiver 120 transmits to the transmitter 102 information identifying the amount of power;
    • a switch module 330 for signaling when to open a switch of the power harvesting circuity 310 in order to stop power surges from damaging sensitive components. In some embodiments, as discussed below with reference to FIGS. 5A-5B, the switch is a negative voltage switch that is in a default-closed state;
    • A toggle module 332 for controlling the impedance mismatch in the system, which in turn can cause a portion of the incoming power to be reflected from the antenna of the wireless power receiver. By modulating the amount of power reflected by the antenna device can communicate with a wireless power transmitter without needing a dedicate communication component (e.g., ., IEEE 802.15.4, Wi-Fi, ZigBee, 6LoWPAN, Thread, Z-Wave, Bluetooth Smart, ISA100.11a, WirelessHART, MiWi, etc.) wired protocols (e.g., Ethernet, HomePlug, etc.). In some embodiments, as discussed with reference to FIGS. 6A-6C below, when the toggle 602 toggles it causes the adjustable load 601 to change the impedance of the receiver 120, which further causes incoming power to be reflected at antenna 413; and
    • database 322, including but not limited to:
      • sensor information 324 for storing and managing data received, detected, and/or transmitted by one or more sensors (e.g., sensors 128 and/or one or more remote sensors);
      • device settings 326 for storing and managing operational settings for the receiver 120, a coupled electronic device (e.g., an electronic device 122), and/or one or more remote devices; and
      • communication protocol information 328 for storing and managing protocol information for one or more protocols (e.g., custom or standard wireless protocols, such as ZigBee, Z-Wave, etc., and/or custom or standard wired protocols, such as Ethernet).

In some embodiments, the power receiving module 320 communicates the amount of power to the communication module 316, which communicates the amount of power to other remote devices (e.g., transmitter 102, FIGS. 1-2). Moreover, in some embodiments, the power receiving module 320 may communicate the amount of power to database 322 (e.g., the database 322 stores the amount of power derived from one or more power waves 116). In some embodiments, the power receiving module 321 instructs the communication module 316 to transmit distinct transmissions to the remote devices (e.g., a first communication signal that indicates a first amount of power received by the receiver (e.g., by a first test signal from the transmitter 102), a second communication signal that indicates a second amount of power received by the receiver (e.g., by a second test signal from the transmitter 102), and so on if needed). Alternatively, in some embodiments, the power receiving module 320 instructs the communication module 316 to transmit data packets to the remote devices (e.g., a respective data packet can include information for multiple test signals transmitted by the transmitter 102).

Each of the above identified elements (e.g., modules stored in memory 142 of the receiver 120) is optionally stored in one or more of the previously mentioned memory devices, and corresponds to a set of instructions for performing the function(s) described above. The above identified modules or programs (e.g., sets of instructions) need not be implemented as separate software programs, procedures, or modules, and thus various subsets of these modules are optionally combined or otherwise rearranged in various embodiments. In some embodiments, the memory 142, optionally, stores a subset of the modules and data structures identified above. Furthermore, the memory 142, optionally, stores additional modules and data structures not described above, such as an identifying module for identifying a device type of a connected device (e.g., a device type for an electronic device 122).

On-and-Off Power Detection

FIG. 4A is a schematic of a representative receiver 120 in accordance with some embodiments. The representative receiver 120 is an example of the receiver 120 (FIG. 3). The components in FIG. 4A are illustrated in a particular arrangement for ease of illustration and one skilled in the art will appreciate that other arrangements are possible. Moreover, while some example features are illustrated, various other features have not been illustrated for the sake of brevity and so as not to obscure pertinent aspects of the example implementations disclosed herein.

In FIG. 4A, the receiver 120 includes an antenna 413 capable of receiving wireless power transmission signals (e.g., power waves 116). Once the wireless power transmission signals are received at the antenna 413 and converted to an alternating current, the alternating current is sent to an input of the coupling mechanism 410. Some examples of coupling mechanism 410 are illustrated in FIG. 4C. In some embodiments, the coupling mechanism 410 has two outputs (a first output that supplies AC alternating current the first rectifier 401, and a second output that supplies the alternating current to the second rectifier), and each output receives a portion of the alternating current received at the input of the coupling mechanism. In some embodiments, the coupling mechanism is configured to send all but −30 dB to −40 dB of the alternating current to the first output of the coupling mechanism 410, and sending the remaining −30 to −40 dB of the alternating current to the second output of the coupling mechanism 410.

The first output of the coupling mechanism 410 is coupled to an input of an input matching network 403, which is configured to match the impedance of the first rectifier with the impedance of the antenna 413. Although one matching network 403 is shown, it is possible to have multiple input matching networks, as illustrated by numeral 403-n in FIG. 4B. The matching network is designed to match the impedance between the source (e.g., the antenna 413) and the load (e.g., the rectifier 401). The output of the matching network(s) is (are) coupled to the first rectifier 401. The first rectifier is configured to convert all but −30 dB to −40 dB of the alternating current to direct current. Some examples of rectifiers are shown in FIG. 4D. The output of the first rectifier 401 is coupled in parallel to both a capacitor 404, and the charging components ZL 406. The capacitor 404, which is also coupled to the ground, is designed to reduce ripple in the direct current output by the first rectifier 401, and has a capacitance that matches a direct current of the output of the first rectifier. With larger loads (i.e., rectifier outputs), a larger capacitance may be required, and when there is a larger capacitance, the capacitor takes a longer time to charge and discharge (i.e., the voltage to reach a steady state), which slows the response time of detecting whether power is no longer being received at the antenna 413.

The second output of the coupling mechanism is coupled to the second rectifier 402. The second rectifier 402 converts the remaining −30 dB to −40 dB of the wireless power transmission signals into direct current. Since this −30 dB to −40 dB is roughly less than 1% of the amount of wireless power transmission signals received at the antenna 413, the capacitor 405 associated with the second rectifier 402 has a lower capacitance (relative to the capacitance of the capacitor 404). Consequently, the capacitor 405 in FIG. 4A can charge up and discharge rapidly in comparison to the capacitor 404 coupled to the output of the first rectifier 401. As a result, the direct current and/or voltage measuring components (“VAUX”) 409-1 detect changes in direct current power levels and/or voltage levels in a shorter time span than the measuring components included in the charging components ZL 406. The measuring components (“VAUX”) 409-1 detect the change in wireless power transmission signals by either a change in voltage and/or direct current, and can then instruct the charging components ZL 406 components to prepare for a change in power once the capacitor 404 is either discharging or fully charged.

The second rectifier 402 is also optionally coupled with two resistors in series (resistor 407 and resistor 408). Between these two resistors, a voltage measurement can also be taken, which acts as another measurement component (“VAUX_DIV”) 409-2. Such an arrangement of resistors is capable of stepping down the voltage, which allows for measuring components to have a lower voltage threshold to determine whether power is increasing or no longer being received. The resistance of these resistors can be varied depending on the acceptable voltage level of the direct current measuring components. In some embodiments, these resistors are variable resistors and are adjusted by a control. Furthermore, resistor 408 is also coupled to the ground.

To help illustrate the benefits of a dual rectifier receiver, graph 400-A compares a single rectifier system against a dual rectifier system. The graph shows at time “t1” that the RF power (i.e. the wireless power transmission signals) starts to be received at the antenna 413. “VOUT” shows the output of direct current at the output of the first rectifier. “VAUX” shows the measuring component 409-1, which shows the output of the second rectifier 402. And, “VAUX_DIV” shows a second measurement point 409-2 that has had its voltage stepped down by the two resistors, which can be used to activate a measuring component that has a lower voltage threshold.

Moving to time “t2” the received RF power input remains constant and does not change. At time “t2,” the “VOUT” measuring components are still seeing a rise in voltage, as opposed to a constant voltage. Only once the voltage has settled can the system utilize the converted direct current (DC) (power). While the system is waiting for the voltage to settle, it is not aware that incoming power is going to the charging components ZL 406. To counteract this undesirable effect of not preparing the charging components ZL 406 for the incoming power, a second rectifier 402 is used in conjunction with a capacitor 405 with a smaller capacitance (relative to capacitor 404) that allows the voltage to settle at time “t2.” Once the voltage has settled at measuring components 409-1 and 409-2, then the system can communicate with the charging components ZL 406, (e.g., warn those components that incoming power is coming despite “VOUT” not yet being settled).

Only at time “t3” does the first rectifier and capacitor 404 produce a settled voltage that can be used by the system. At time “t3,” the RF power is no longer being received at the antenna 413. At time “t4,” the smaller capacitance capacitor 405 is able to settle to a voltage level that indicates that there is no longer any RF power being received at the antenna 413 (e.g., 0 volts). Once this lower voltage settles, the control system can notify the charging components ZL 406 that they should prepare for powering down. In contrast, at time “t5” (i.e., long after time “t4”), the larger capacitance capacitor 404 fully discharges and settles to the lower voltage indicating the system is no longer receiving RF power at the antenna 413. In sum, the charging components of the wireless power receiver benefit from an early warning from the smaller capacitor 405 that power is no longer being received because the charging components avoid having to wait on the capacitor's 404 long discharge time before beginning shutdown. Consequently, the early warning from the smaller capacitor 405 allows the charging components to prepare for a power down in anticipation of a loss of power, thus prolonging a life of the wireless power receiver (and potentially components in the device to be charged).

Thus, FIG. 4A at bottom describes a receiver 120 that can apportion a small amount of its received wireless power for the purpose of improving reliability of the main components of the circuit (i.e., ZL 406 components) by warning these components that a change in power is occurring. This improved reliability is achieved by anticipating a shutdown, which is discussed in detail in the preceding paragraph.

FIG. 4B is a schematic that illustrates alternative embodiments to those discussed with reference to FIG. 4A. Namely, FIG. 4B shows alternative locations at which the coupling mechanism 410 can be coupled to the circuit, and still perform the same on-and-off detection as discussed in detail with respect to FIG. 4A. While some example features are illustrated, various other features, which were shown in FIG. 4A, have not been illustrated in FIG. 4D for the sake of brevity and so as not to obscure pertinent aspects of the example implementations disclosed herein.

The differences between FIG. 4A and FIG. 4B include the addition of first capacitor 404-a and second capacitor 404-b, and at least a second matching network identified as Nth input matching network 403-n. Additionally, four vertical dotted lines represent the different locations that the coupling mechanism 410 can be coupled to the circuit. As shown, the coupling mechanism can be coupled to the circuit at a point before a first capacitor 404-a. Alternatively, the coupling mechanism 410 may also be coupled after the first capacitor 404-a, but before the second capacitor 404-b. The next location at which the coupling mechanism 410 can be coupled to the circuit is the same location as the one shown in FIG. 4A. Finally, the coupling mechanism 410 can be coupled to the circuit between any of the input matching networks. This is illustrated by the coupling mechanism 410 being placed after the input matching network 403, but before the coupling mechanism 4′0 being placed before the Nth input matching network 403-n. In this example, the Nth input matching network 403-n represents the last input matching network.

FIG. 4C is schematic illustrating three separate coupling mechanism embodiments. In some embodiments, the coupling mechanism 410 is a directional coupler, shown in FIG. 4C as “Coupler A.” The directional coupler consists of two separate paths, the first path 458 and the second path 459. With reference to both FIG. 4A and FIG. 4B, the first path 458 is the path that is coupled to the antenna 413. Path 458 is also ultimately connected to the first rectifier 401. The second path 459 is placed within a certain proximity to the first path 458 so as to allow a portion of the RF signals to bleed off to the second path 459. The second path 459 is ultimately coupled to the second rectifier 402, as shown in FIG. 4A. Additionally, the second path 459 includes a resistor 456 that is coupled to a ground 457.

FIG. 4C also includes schematics for illustrating a capacitive coupler, shown in FIG. 4C as “Coupler B.” The capacitive coupler consists of two separate paths, the first path 460 and the second path 461. With reference to both FIG. 4A and FIG. 4B, the first path 460 is the path that is coupled to the antenna 413. Path 460 is also ultimately connected to the first rectifier 401. The second path 461 is coupled between the first capacitor 462 and second capacitor 463. The second path 461 is ultimately coupled to the second rectifier 402, as shown in FIG. 4A. Additionally, the second capacitor 463 is also coupled to a ground 464.

FIG. 4C also includes schematics for illustrating a resistive coupler, shown in FIG. 4C as “Coupler C.” The capacitive coupler consists of two separate paths, the first path 465 and the second path 466. With reference to both FIG. 4A and FIG. 4B, the first path 465 is the path that is coupled to the antenna 413. Path 465 is also ultimately connected to the first rectifier 401. The second path 466 is coupled between the first resistor 467 and second resistor 468. The second path 466 is ultimately coupled to the second rectifier 402, as shown in FIG. 4A. Additionally, the second resistor 486 is also coupled to a ground 469.

FIG. 4D shows two schematics for rectifiers. Rectifier “A” illustrates a diode based rectifier. With respect to the diode based rectifier, the input to the rectifier system is shown as input 448, which is coupled to an anode of a diode 450, and coupled in parallel to the cathode of a diode 451. The cathode of the diode 450 is coupled to the output of the rectifier system, as shown as output 449, while the anode of the diode 451 is coupled to the ground 452.

FIG. 4D also shows a schematic for a second rectifier, rectifier “B.” Rectifier “B” is a diode connected transistor based rectifier. With respect to diode connected transistor based rectifier, the input to the rectifier system is shown as input 448, which is coupled, in parallel, to a first diode connected transistor 453, and a second diode connected transistor 454. The first diode connected transistor 453 is coupled to the output of the rectifier system, as shown as output 449, while the second diode connected transistor 454 is coupled to the ground 455.

FIG. 4E shows a schematic of a receiver 120 that is similar to the receiver shown in FIG. 4A. The receiver shown in FIG. 4E, however, does not include a coupling mechanism. The purpose of the circuit shown in FIG. 4E is for detecting when the wireless power transmission signals are no longer being received at the antenna 413, without the use of a coupling mechanism. When the power is no longer detected the receiver can warn components that are coupled to the output of the first rectifier 401 that the charging components 406 need to prepare for shutdown.

The schematic itself shows an antenna 413 that is coupled to an input of an input matching network 403. The output of the input matching network 403 is coupled to two rectifiers 401, 402 in parallel. Some examples of more simplified rectifiers are shown in FIG. 4F. The output of the rectifier 401 is coupled in parallel to the both a capacitor 404 and charging components “ZL” 406. The capacitor 404, which is also coupled to the ground 438, is designed to reduce ripple in the DC output by the first rectifier 401, and has a capacitance that matches the DC load of the output of the first rectifier 401. With larger loads, a larger capacitance is required, and with the larger capacitance, the capacitor 404 takes a longer time to charge and discharge (i.e., for the voltage to reach a steady state), which slows the response time of detecting whether power is no longer being received at the antenna 413.

The second output of the input matching network 403 is coupled to the second rectifier 402. The capacitor 405 in FIG. 4E can charge up and discharge more rapidly in comparison to the capacitor 404 coupled to the output of the first rectifier 401. With respect to the ripple from the output of the rectifier 402, the components coupled to the output of the rectifier 402 require a less drastic ripple reduction as compared to the components coupled to the output of the rectifier 401. As a result, a smaller capacitance capacitor 405 can be used that allows for faster discharge times and, consequently, the DC and/or voltage measuring components (“VAUX”) 409-1 detect changes in DC power levels and/or voltage levels in a shorter time span than the measuring components included in the charging components ZL 406. The measuring components (“VAUX”) 409-1 detect the change in wireless power transmission signals by a change in voltage and/or DC current, and can then instruct the charging components ZL 406 to prepare for a change in power once the capacitor 405 either starts discharging or is fully discharged.

In some embodiments, the second rectifier 402 is also optionally coupled to two resistors in series (resistor 407 and resistor 408, which are coupled to the ground 437). Between these two resistors a voltage measurement can also be taken, which acts as another measurement component (“VAUX_DIV”) 409-2. Such an arrangement of resistors is capable of stepping down the voltage, which allows for measuring components to have a lower voltage threshold to determine whether power is no longer being received. The resistance of these resistors can be varied depending on the acceptable voltage level of the DC measuring components. In some embodiments, these resistors are variable resistors and are adjusted by a control.

To help illustrate the benefits of a dual rectifier receiver, graph 400-B compares a single rectifier system to a dual rectifier system. The graph shows at time “t1” that RF power (i.e. wireless power transmission signals) are received at the antenna 413. “VOUT” shows the output of DC at the output of the first rectifier. “VAUX” shows the measuring component 409-1, which shows the output of the second rectifier 402. And, “VAUX_DIV” shows a second measurement point 409-2 that has had its voltage stepped down by the two resistors, which can be used to activate a measuring component that has a lower voltage threshold.

At time “t2”, the first rectifier 401 and capacitor 404 produce a settled voltage that can be used by the charging components ZL 406. Also at time “t2”, the RF power is no longer being received at the antenna 413. At time “t3”, the smaller capacitance capacitor 405 is able to settle to a voltage level that indicates that there is no longer any RF power being received at the antenna 413. Once this lower voltage settles (e.g., at 0 volts), the system can notify the charging components ZL 406 that they should prepare for powering down. In contrast, it is not until time “t4” that the larger capacitor 404 fully discharges and settles to the lower voltage indicating the system is no longer receiving RF power at the antenna 413. Warning (i.e., signaling) the charging components that RF power is no longer being received is beneficial so that those components can prepare for a shutdown in anticipation of a loss of power. Without the second rectifier 402, the charging components would have to rely solely on the first rectifier 401 and the larger capacitor 404 to prepare for shutdown, which as explained above is not ideal because the larger capacitor 404 takes a significant amount of time to fully discharge (i.e., an adequate warning cannot be given to the charging components when the larger capacitance capacitor 404 is solely relied upon).

In sum, FIG. 4E ultimately describes a receiver 120 that can apportion a small amount of its received wireless power for the purpose of improving reliability of the main components of the circuit (i.e., ZL 406 components) by warning these components that the RF power is no longer being received at the antenna 413.

Transitioning to FIG. 4F, FIG. 4F illustrates two simplified rectifiers that are optionally used in rectifiers 401 and 402 in FIG. 4E. These simplified rectifiers are similar to those shown in FIG. 4D, however, since the input of the first rectifier is couple to the input of the second rectifier, the second rectifier can be made simpler. Although FIG. 4F shows examples of some rectifiers, any possible diode connected configuration which has reverse bias cut-off characteristics can be used instead. With respect to the second rectifier 402, in some embodiments the second rectifier 402 is on the same or separate integrated circuit as the first rectifier (i.e., main rectifier) 401. The second rectifier (i.e., auxiliary rectifier) 402, in some embodiments, is a discrete system on a printed circuit board, package, and/or module.

Power Surge Protection

FIG. 5A is a schematic of a representative receiver 120 in accordance with some embodiments. The representative receiver 120 is an example of the receiver 120 (FIG. 3). The components in FIG. 5A are illustrated in a particular arrangement for ease of illustration and one skilled in the art will appreciate that other arrangements are possible. Moreover, while some example features are illustrated, various other features have not been illustrated for the sake of brevity and so as not to obscure pertinent aspects of the example implementations disclosed herein.

In FIG. 5A, the receiver 120 includes an antenna 413 capable of receiving wireless power transmission signals (also referred to as RF power). Once the wireless power transmission signals are received at the antenna 413 and converted to an alternating current, the alternating current is sent to an input of the coupling mechanism 410. Some examples of coupling mechanism 410 are illustrated in FIG. 4C. In some embodiments, the coupling mechanism 410 has two outputs (a first output that supplies the alternating current to the first rectifier, and a second output that supplies the alternating current to the second rectifier), and each output receives a portion of the alternating current received at the input of the coupling mechanism 410. In some embodiments, the coupling mechanism 410 is optionally configured to send all but −30 dB to −40 dB of the alternating current to the first output of the coupling mechanism 410, and sending the remaining −30 to −40 dB of the alternating current to the second output of the coupling mechanism 410.

A first output of the coupling mechanism 410 is coupled to an input of an input matching network 403, which is configured to match the impedance of the rectifier 401 with the impedance of the antenna 413. Additionally, it is possible to have multiple input matching networks, as illustrated by numeral 403-n. The matching network is designed to match the impedance between the source (e.g., the antenna) and the load (e.g., the rectifier). The output of the matching network(s) is coupled to the first (i.e., primary) rectifier 401. The output of the rectifier 401 is coupled to a capacitor 503. The capacitor 503, which is also coupled to the ground 504, is designed to reduce ripple in the system, and has a capacitance that matches the DC load of the output of the first rectifier 401. With larger loads, a larger capacitance is required to reduce the ripple, so as to not damage the charging components represented by numeral 505.

A second output of the coupling mechanism 410 is coupled to the second rectifier 510 (also referred to as an auxiliary or secondary rectifier). The second rectifier 510 (also referred to as the negative voltage generator) converts its received wireless power transmission signals into negative voltage. The output of the second rectifier 510 is coupled to a “normally on” active switch 501 that has a gate voltage of 0 volts when turned on (i.e., a switch that is in a normally closed state that couples the circuit to the ground 502, which causes an impedance mismatch between the rectifier 401 and the antenna 413, which in turn causes the wireless power transmission signals to be reflected by the antenna). The switch 501, when coupled to the ground 502, pulls the output of the rectifier 510 to 0 volts. In other words, when the voltage falls below 0 volts, the switch 501 will gradually begin to open, which causes some of the negative voltage to not be directed to the ground 502, but instead back to the first output of the coupling mechanism 410. Optionally, as depicted by FIG. 5A, the output of the rectifier 510 can be coupled either to the first output of the coupling mechanism 410, before or after the input matching network, between two or more matching networks, or before or after the first rectifier 401. When the switch 501 allows for some of the current to be directed to the ground 502, an impedance mismatch is created between the antenna and the first rectifier 401. Once the gate 501 is fully opened and the current with the negative voltage is no longer being directed to the ground, then the first rectifier 401 can match the impedance of the antenna 413, and the wireless power transmission signals will not be reflected by the antenna 413.

To illustrate the discussion above, graph 500 shows the gradual opening of the switch 501 stopping the rectifier 401 from receiving a power surge. As shown in the first top row 500-A of the graph 500, the RF input power (i.e., the wireless power transmission signals that are converted to an alternating current) is received at the antenna 413. The wireless power transmission signals are constant beginning at time “t1.” The second row 500-B, “Vi_coupled,” illustrates the amount of wireless power transmission signals harvested by the antenna 413 (and converted to the alternating current), and subsequently apportioned by the coupling mechanism 410. Numeral 506 illustrates the point at which “Vi_coupled” is measured. “Vi_coupled” is constant at time “t1,” which corresponds to the amount of wireless power transmission signals being received at the antenna 413. However, only a portion of the power is received at “Vi_coupled” because of the coupling mechanism 410. Even at time “t2”, the amount of the alternating current measured at “Vi-Coupled” remains constant, due to the coupling mechanism's 410 apportionment. In some embodiments, the coupling mechanism 410 can dynamically adjust the amount of power that is sent to the negative voltage rectifier 510.

The third row 500-C of graph 500 illustrates the negative voltage measured at point 507 in the circuit illustrated in FIG. 5A. At time “t1,” which is the same time that the antenna 413 started to receive the alternating current, the rectifier 510 (e.g., a negative voltage generator) begins converting the alternating current to a negative voltage. The negative voltage slowly starts to increase in magnitude until time “t2,” which at that point the negative voltage has reached a negative voltage threshold.

The fourth row 500-D illustrates the QR switch's (i.e., the switch 501) status. In other words, the fourth row 500-D shows that, depending on the negative voltage produced by the negative voltage generator 510, the switch 501 can exist in an on state (“ON”), a partially-on state that is below the negative voltage threshold (“Sub_Vth”), and a completely off state (“OFF”). At any time where the receiver does not receive any wireless power transmission signals, the switch 501 will be in the “ON” state, and will direct incoming current to the ground 502 causing an impedance mismatch at the rectifier 401. This impedance mismatch causes the wireless power transmission signals to be reflected at the antenna 413. At time “t1”, the alternating current starts to be received at the negative voltage generator 510, and then the negative voltage generator 510 starts producing negative voltage, as discussed above with reference to the row 500-C. Once the negative voltage starts being produced, the switch 501 begins to open, which gradually uncouples the circuit at that point from the ground 502. At time “t2”, the negative voltage threshold is met, and the switch 501 is completely open and no longer couples the ground 502 to the circuit. This consequently reduces the impedance mismatch between the first rectifier 401 and the antenna 413, and results in less reflection of the wireless power transmission signals.

The fifth row 500-E of graph 500 illustrates the amount of power that is either reflected or received at the antenna 413 due to the impedance mismatch caused by the switch either being coupled, partially coupled, or uncoupled with the ground 502. Specifically, at time “t1”, the amount of the wireless power transmission signals reflected is at its highest, meaning that all but the wireless transmission signals apportioned by the coupling mechanism 410 to be sent to the negative voltage generator 510 are reflected at the antenna 413, which is caused by the impedance mismatch between the antenna 413 and the first rectifier 401. As the switch 501 begins to open between times “t1” and “t2”, the impedance mismatch begins to decrease, and as the mismatch begins to decrease, the wireless power transmission signals are reflected at a lesser rate. When the wireless power transmission signals are no longer reflected, they are directed to the first rectifier 401. After time “t2”, the voltage threshold of the switch 501 is met the amount of reflected wireless transmission signals is decreased to its lowest state.

The sixth row 500-F of graph 500 illustrates the amount of wireless power transmission signals converted to direct current (“VRECT”) by the first rectifier 401. The measuring point of “VRECT” occurs at point 509. At time “t1”, the rectifier 401 rectifies a portion of the alternating current received at the antenna 413 corresponding to the impedance mismatch caused the state of the switch 501. Additionally, at time “t1”, the switch 501 is still primarily coupled to the ground 502, and consequently, the impedance mismatch is still high, meaning that the wireless power transmission signals are reflected by the antenna 413. Since the majority of the wireless power signals are being reflected, the rectifier 401 is not capable of producing a large amount of rectified power. At time “t2”, when the switch 501 is no longer coupled to the ground 502, the impedance mismatch between the rectifier 401 and the antenna 413 is eliminated, thereby allowing the rectifier 401 to receive the alternating current from the antenna 413.

The seventh row 500-G of graph 500 illustrates measuring point 508 in FIG. 5A. Specifically, row 500-G illustrates what current would be received at the input of the rectifier 401 without the negative voltage generator 510 and switch 501 (i.e. the surge protector components). In the graph 500, the current that is received at the input of the rectifier 401 is referred to as “IRIN without surge protection.” As shown in row 500-G, after time “t1” a large current spike is shown, which can cause damage to the first rectifier 401, and other related charging components. After the current spike, the current plateaus and no longer has any large variations in magnitude.

The eighth row 500-H of graph 500 illustrates detected current at measuring point 508 in FIG. 5A. Specifically, row 500-G shows the measurement of the current that is received at the input of the rectifier 401, when the negative voltage generator 510 and switch 501 (i.e. the surge protector components coupled to the circuit) stop surges in power. This is shown to contrast row 500-G, which shows the current that would be flowing to the rectifier 401 if there was no surge protection. In the graph, the current with surge protection is referred to as “IRIN with surge protection.” As shown in 500-H, after time “t1” a gradual increase in current is shown, instead of a large spike as shown in 500-G, that reduces damage to the first rectifier 401 and other related components. After the switch 501 is fully opened the current plateaus and no longer has any large variations in its magnitude.

FIG. 5B is a schematic that illustrates alternative embodiments to those presented in FIG. 5A. Namely, FIG. 5B shows alternative locations at which the coupling mechanism 410 can be coupled to the circuit, and still perform the same surge protection as discussed in detail with respect to FIG. 5A. While some example features are illustrated, various other features, which were shown in FIG. 5A, have not been illustrated in FIG. 5B for the sake of brevity and so as not to obscure pertinent aspects of the example implementations disclosed herein.

The differences between FIG. 5A and FIG. 5B include the addition of first capacitor 404-a and second capacitor 404-b, and at least a second matching network identified as Nth input matching network 403-n. Additionally, six vertical dotted lines represent the different locations that the coupling mechanism 410 can be coupled to the circuit. As shown, the coupling mechanism 410 can be coupled to the circuit at a point before a first capacitor 404-a. Alternatively, the coupling mechanism 410 may be coupled after the first capacitor 404-a, but before the second capacitor 404-b. The next location at which the coupling mechanism 410 can be coupled to the circuit is at the same location as the one shown in FIG. 5A. The coupling mechanism 410 can be coupled to the circuit between any of the input matching networks. This is illustrated by the coupling mechanism 410 being placed after the input matching network 403, but before the coupling mechanism 410 being placed before the Nth input matching network 403-n. In this example, the Nth input matching network 403-n represents the last input matching network. The coupling mechanism 410 can also be placed after the last input matching network in the series of input matching networks, but before the first rectifier 401. Finally, the coupling mechanism 410 may also be placed after the rectifier 401, but before the capacitor 404 and ZL 406, which represent the charging components that the receiver is coupled to.

In-Band Communication

Transitioning to FIG. 6A, FIG. 6A illustrates a way for in-band communication between a wireless power receiver 120 and a wireless power transmitter 102 without a dedicated communication radio for controlling the power of the wireless power transmission signals. The components in FIG. 6A are illustrated in a particular arrangement for ease of illustration and one skilled in the art will appreciate that other arrangements are possible. Moreover, while some example features are illustrated, various other features have not been illustrated for the sake of brevity and so as not to obscure pertinent aspects of the example implementations disclosed herein.

FIG. 6A's schematic illustrates one embodiment of a receiver 120. Receiver 120 includes an antenna 413 capable of receiving wireless power transmission signals. Once the wireless power transmission signals are received at the antenna 413 and converted to an alternating current, the wireless power transmission signals are sent to an input of the coupling mechanism 410. Some examples of coupling mechanism 410 are illustrated in FIG. 4C. The coupling mechanism 410 has two outputs (a first output that supplies alternating current to the first rectifier 401, and a second output that supplies alternating current to the second rectifier 402), and each output receives a portion of the alternating current received at the input of the coupling mechanism 410. In some embodiments, the coupling mechanism 410 is optionally configured to send all but −30 dB to −40 dB of the alternating current to the first output of the coupling mechanism 410, and sending the remaining −30 to −40 dB of the alternating current to the second output of the coupling mechanism 410.

A first output of the coupling mechanism 410 is coupled to an input of an input matching network 403, which is configured to match the impedance of the rectifier 402 with the impedance of the antenna 413. Additionally, it is possible to have multiple input matching networks, as illustrated by 403-n in FIG. 6B. The matching network is designed to match the impedance between the source (e.g., the antenna 4123) and the load (e.g., the rectifier 401). The output of the matching network(s) is (are) coupled to the first (i.e., primary) rectifier 401. The output of the first rectifier 401 is coupled in parallel to the both a capacitor 404 and ZL 406, which represent the charging components that the receiver is coupled to. The capacitor 404, which is also coupled to the ground, is designed to reduce ripple of the direct current output by the first rectifier 401 in the system, and has a capacitance that matches the direct-current load of the output of the first rectifier 401. With larger loads (i.e., the rectifier output), a larger capacitance is required, and when there is a larger capacitance, the capacitor takes a longer time to charge and discharge (i.e., for voltage to reach a steady state), which slows the response time of detecting whether power is no longer or is being received at the antenna 413.

A second output of the coupling mechanism 410 is coupled to another input matching network 414. A second rectifier 402 (also referred to as an auxiliary or secondary rectifier) is coupled to the output of the other (also referred to as the auxiliary input matching network) input matching network 414. The second rectifier 402 converts the apportioned alternating current received from the coupling mechanism 410 to direct current with a voltage component. The second rectifier 402 is coupled to an adjustable load 601 that can cause a slight impedance mismatch of the other matching network 414. This ultimately causes a portion of wireless transmission signals to be reflected by the antenna 413 back to the transmitter 102. The adjustable load 601 is coupled to a toggle 602, and when the toggle 602 is toggled, it causes the adjustable load 601 to be toggled between two different impedances. The purpose of such an adjustable load 601 is to modulate the amount of power reflected by the receiver 120 in order to communicate with the transmitter 102.

As previously discussed, input matching quality of an RF system determines the amount of power reflected from the antenna 413. In a perfectly matched system there is no reflected power. However, when there is an impedance mismatch, some of the wireless power transmission signals are reflected from the antenna 413. Reflected wireless power transmission signals can be detected with a RF signal receiving circuitry at the transmitter 102. These reflected signals can be used by the transmitter 102 to determine how much power to send to the receiver 120, or when to stop transmitting power to the receiver 120 (e.g., the battery is sufficiently charged and no longer needs to receive power). To communicate with the transmitter 102, the receiver 120 needs to modulate the impedance (i.e., so that the reflected signals convey information). This process will be further discussed in relation to the graph 600 in FIG. 6A.

FIG. 6A's graph 600 demonstrates how the receiver 120 is able to communicate with the transmitter 102 by modulating its impedance at the auxiliary matching network. FIG. 6A includes a first row 600-A illustrating the amount of RF power (also referred to as wireless power transmission signals) that the antenna 413 is receiving. Between time “t1” and “t3”, there is no impedance mismatch, and the full amount of wireless power transmission signals is received by the antenna 413 (e.g., no signals are reflected at the antenna 413). However, at time “t3” to “t4”, an impedance mismatch is introduced into the system, which results in the amount of RF power received by the antenna 413 to decrease (i.e., some signals are reflected at the antenna 413). As shown at times “t4” and “t5”, the toggle 602 (also referred to as “VCTR”), is switched on and off causing the reflection of wireless power transmission signals to be modulated from no reflection to partial reflection. Various aspects of the “VCTR” such as frequency, duty cycle, pulse width and patterns can be used as a form of signal generation (e.g., modulation). This modulation can be used to communicate with the transmitter 102 by interpreting certain modulations as instructions regarding, e.g., how much power the transmitter 102 should be sending to the receiver 120. In some embodiments, as illustrated in row 600-A, the modulation received between times “t4” to “t5” causes the transmitter 102 to stop transmitting wireless transmission signals. As a result, after time “t5” the antenna 413 no longer receives wireless power transmission signals from the transmitter 102. In some embodiments, the transmitter 102 includes a demodulator that allows the transmitter 102 to demodulate and process the modulated signals generated by the receiver 120. The modulated signals can provide other information in addition to a power requirement for the receiver 120. For example, the modulated signals indicate a location of the receiver 120 relative to the transmitter 102. In another example, the modulated signals may be associated with an authorization key for the receiver 120 (i.e., once the transmitter 102 receives and processes the authorization key, the transmitter 102 initiates wireless charging of the receiver 120). Various other forms of information may conveyed using the modulated signals discussed herein.

In FIG. 6A's graph 600, the second row 600-B shows the voltage that rectifier 401 is outputting. This measurement point is taken after the capacitor 404, and is represented by numeral 603 in the circuit schematic in FIG. 6A. Between times “t1” and “t2”, the capacitor 404 is charging up, and only once fully charged does the voltage plateau and remain at a constant magnitude. Between times “t3” and “t4”, the impedance is adjusted. This impedance adjustment, however, is made only in relation to the other input matching network 414, which means that the alternating current sent to the first rectifier 401 by the coupling mechanism 410 remains the same. Therefore, between times “t3” and “t5”, the rectifier 401 is able to output the same amount of rectified power despite toggle 602 toggling the impedance of the other input matching network 414.

In FIG. 6A's graph 600, the third row 600-C shows the toggle 602 (also referred to as the (“VCTR”)) toggling the load impedance of the input matching network 414. From times “t1” to “t3”, the toggle 602 is in a first state causing a certain load impedance. In some embodiments, there is no load impedance between the antenna 413 and the other input matching network 414, and none of the wireless power transmission signals are reflected by the antenna 413. Between times “t3” and “t4”, the toggle 602 is in a second state that causes a certain load impedence. The load impedance generated by the toggle 602 being toggled results in a mismatch with the antenna's 413 impedance, which causes a portion of the wireless power transmission signals to be reflected back to the transmitter 102. This reflected portion of the wireless power transmission signals is normally not reflected by the antenna 413 (e.g., when the toggle is in the first state).

In FIG. 6A's graph 600, the fourth row 600-D shows the output voltage by the second rectifier 402 in response to the toggling of the load impedance of the input matching network 414. The point at which the output voltage of the second rectifier 402 is demonstrated by numeral 604 in FIG. 6A's circuit schematic. Between times “t1” and “t3”, the toggle 602 is in the first state (i.e., no impedance mismatch with antenna 413) while between times “t3” to “t4”, the toggle 602 is in the second state. Again, when the toggle 602 is in the second state, the impedance mismatch is greater at the other input matching network 414, and when the impedance mismatch is greater, a greater percentage of the wireless power transmission signals are reflected by the antenna 413.

In FIG. 6A's graph 600, the fifth row 600-E shows the amount of wireless power transmission signals that are reflected by antenna 413 when the toggle 602 is in the second state. In some embodiments, when the toggle 602 is in the first state (discussed above), the toggle 602 causes the adjustable load 601 to be adjusted and cause a perfect impedance match between the other input matching network 414 and the antenna 413, which is illustrated by times “t1” to “t3” and portions of “t4” to “t5.” At these times, an amount of wireless power transmission signals reflected by the antenna 413 is minimal (if any). At times “t3” to “t4” and portions of time “t4” to “t5,” however, the toggle 602 is in the second state, which causes the adjustable load 601 to be adjusted, which ultimately causes an impedance mismatch between the antenna 413 and the other input matching network 414. When there is an impedance mismatch, at least some of the wireless transmission signals are reflected by the antenna 413, which is shown at times “t3” to “t4” and portions of time “t4” to “t5.” Although two states of modulation are discussed, it is possible to modulate the toggles frequency, duty cycle, pulse, width, and patterns.

FIG. 6B is a schematic that illustrates alternative embodiments to those presented in FIG. 6A. Namely, FIG. 6B shows alternative locations at which the coupling mechanism 410 can be coupled to the circuit and still perform the same in-band communication techniques discussed in detail with respect to FIG. 6A. While some example features are illustrated, various other features, which were shown in FIG. 6A, have not been illustrated in FIG. 6B for the sake of brevity and so as not to obscure pertinent aspects of the example implementations disclosed herein.

The differences between FIG. 6A and FIG. 6B include the addition of first capacitor 404-a and second capacitor 404-b, and at least a second matching network that is coupled to the first rectifier 401, which is identified as Nth input matching network 403-n. Additionally, five vertical dotted lines represent different locations that the coupling mechanism 410 can be coupled to the circuit. As shown, the coupling mechanism 410 can be coupled to the circuit at a point before a first capacitor 404-a. Alternatively, the coupling mechanism 410 may be coupled after the first capacitor 404-a, but before the second capacitor 404-b. The next location at which the coupling mechanism 410 can be coupled to the circuit of receiver 120 is at the same location as the one shown in FIG. 6A. The coupling mechanism 410 can be coupled to the circuit between any of the input matching networks. This is illustrated by the coupling mechanism 410 being placed after the input matching network 403, but before the coupling mechanism 410 being placed before the Nth input matching network 403-n. In this example, the Nth input matching network 403-n represents the last input matching network. Finally, the coupling mechanism 410 can be placed after the last input matching network in the series of input matching networks, but before the first rectifier 401.

Finally, FIG. 6C illustrates three separate embodiments for adjusting the load of the adjustable load 601, two of which are digital adjustable loads, and one of which that is an analog adjustable load. In some embodiments, a single bit digital control can be used. In some other embodiments, multiple bits can be utilized to increase the resolution/range of the signals that are being generated by the circuit (as shown in in the circuit schematic of FIG. 6A). Although three embodiments are shown, any equivalent means for adjusting the load can also be used instead. In some embodiments, the adjustable load is a tapped switch with a series of resistors, which is shown in the adjustable load 601-A. Looking at adjustable load 601-A, it includes an input point 616, which corresponds to the input of the adjustable load where the adjustable load 601-A receives rectified power from the second rectifier 402, as shown in FIG. 6A's circuit schematic. The input point 616 is coupled in parallel to the input of a capacitor 617 and an input of a resistor 619. The output of the capacitor 617 is coupled to the ground 618. The output of the resistor 619 is coupled in parallel to the input of a resistor 620 and the input to a switch 622. The output of the resistor 620 is coupled to the ground 621. The switch 622 switches when the toggle 602 toggles between its two states (e.g., connected to the ground, or unconnected from the ground), as discussed in detail in FIG. 6A. When the toggle 602 causes the switch 622 to connect to the ground 641, the impedance is subsequently changed, which can cause an impedance mismatch between the other input matching network 414 and the antenna 413, as shown in FIG. 6A.

In some embodiments, the adjustable load is a series switch with parallel resistors, which is shown in the adjustable load 601-B. This adjustable load in this example is a digital adjustable load. In some embodiments, a single bit digital control can be used. In some other embodiments, multiple bits can be utilized to increase the resolution/range of the signals that are being generated by the circuit (as shown in in the circuit schematic of FIG. 6A). Looking at adjustable load 601-B, it includes an input point 616, which corresponds to the input of the adjustable load where the adjustable load 601-B receives rectified power from the second rectifier 402, as shown in FIG. 6A's circuit schematic. The input point 616 is coupled in parallel with the input of a capacitor 623, the input of resistor 625, and the input of a resistor 627. The output of the capacitor 623 is coupled to the ground 624. The output of the resistor 625 is coupled to the ground 626. The output of the resistor 627 is coupled to a switch 628. The switch 628 switches when the toggle 602 toggles between its two states (e.g., connected to the ground 629, or unconnected from the ground 629), as discussed in detail in FIG. 6A. When the toggle 602 causes the switch 628 to connect to the ground 629, the impedance is subsequently changed. This causes an impedance mismatch between the other input matching network 414 and the antenna 413, as shown in FIG. 6A.

In some embodiments, the adjustable load is an analog control and load that allows for increased resolution/range of control of the load impedance, which is shown in the adjustable load 601-C schematic. Looking at adjustable load 601-C, it includes an input point 616, which corresponds to the input of the adjustable load where the adjustable load 601-C receives rectified power from the second rectifier 402, as shown in FIG. 6A's circuit schematic. The input point 616 is coupled in parallel to the input of a capacitor 630, the input of resistor of a variable resistor 632, and the input of a resistor 627. The output of the capacitor 623 is coupled to the ground 624. The output of the resistor 625 is coupled to the ground 626. The output of the resistor 627 is coupled to a switch 628. The switch 628 switches when the toggle 602 toggles between its two states (e.g., connected to the ground, or unconnected from the ground), as discussed in detail in FIG. 6A, and the ground 629. When the toggle 602 causes the switch 628 to connect to the ground 629, the impedance is subsequently changed, which can cause an impedance mismatch between the other input matching network 414 and the antenna 413, as shown in FIG. 6A.

FIG. 7 shows a method flowchart 700 that describes a process of communication between a wireless power receiver (e.g., receiver 120 in FIG. 6A) and a wireless power transmitter (e.g., transmitter 102). In FIG. 6A, the receiver 120 includes a rectifier 402 (sometimes called a secondary rectifier or an auxiliary rectifier) that is not used to directly power the main system (e.g., the components that allow the wireless power receiver to use the received energy). One or more operations of the method 700 may be performed by the wireless power receiver or by one or more components thereof (e.g., those described above with reference to FIG. 3). FIG. 7 corresponds to instructions stored in a computer memory or computer-readable storage medium (e.g., memory 142 of the receiver 120, FIG. 3).

In some embodiments, the method flowchart 700 includes receiving (702), by an antenna (e.g., antenna 413, FIG. 6A) of the wireless power receiver, radio frequency (RF) signals from the wireless power transmitter. During the receiving (702) (at least initially), the wireless power receiver substantially matches an impedance of the wireless power transmitter.

Moreover, while receiving the RF signals, the method 700 further includes determining (704) whether a communication criterion is satisfied. In some embodiments, the communication criterion is satisfied when an electronic device serviced by the wireless power receiver is fully charged. Alternatively or in addition, in some embodiments, the communication criterion is satisfied when there is no obstruction (or less than a predetermined level of obstruction) between the wireless power receiver and the wireless power transmitter, and the communication criteria is not satisfied when there is an obstruction (or more than a predetermined level of obstruction). In some instances, obstructions may include one or more of humans, pets, or other items that interfere with the wireless transmission of power, or cause harm to living things.

In some embodiments, in accordance with a determination that the communication criterion is not satisfied (704-No), the method 700 remains unchanged. In other words, the wireless power receiver continues to receive the RF signals from the wireless power transmitter.

In some embodiments, in accordance with a determination that the communication criterion is satisfied (704-Yes), the method 700 includes introducing (706) an impedance mismatch between the wireless power receiver and the wireless power transmitter that causes a portion of the RF signals to be reflected by the receiver's antenna as a modulated signal. In some instances, the wireless power transmitter receives and interprets the modulated signal without using a separate communication radio (e.g., a Bluetooth radio is not needed to interpret the modulated signal). Rather, the wireless power transmitter is able to receive and interpret the modulated signal using the same antenna(s) that transmitted the RF signals in the first place. In some embodiments, the portion can be capped at a certain threshold to stop the receiver from reflecting too much power back to the transmitter.

In some embodiments, introducing (706) the impedance mismatch includes creating (708) one or more impedance mismatches between the wireless power receiver and the wireless power transmitter interspersed with one or more impedance matches between the wireless power receiver and the wireless power transmitter forming the modulated signal. Interspersing impedance matches and mismatches to form a modulated signal is discussed in further detail above with reference to FIGS. 6A-6C.

In some embodiments, the wireless power receiver includes an auxiliary rectifier, coupled to the antenna, that receives some of the RF signals. In such embodiments, introducing (706) the impedance mismatch between the wireless power receiver and the wireless power transmitter includes adjusting a load of the auxiliary rectifier. The auxiliary rectifier may be a rectifier that is composed of: (i) an input configured to receive the second portion of the alternating current, (ii) a first diode, and (iii) a second diode, and the input of the secondary rectifier is coupled to: a cathode of a first diode, wherein an anode of the first diode is coupled to a ground; and an anode of a second diode, wherein a cathode of the second diode is coupled to an output of the secondary rectifier. Alternatively, the auxiliary rectifier may be a rectifier that is composed of: (i) an input configured to receive the second portion of the alternating current, (ii) a first diode-connected transistor, and (iii) a second diode-connected transistor, and the input of the secondary rectifier is coupled to: (a) a first diode-connected transistor, wherein the first diode-connected transistor is connected to a ground, and (b) a second diode-connected transistor, wherein the second diode-connected transistor is connected to an output of the secondary rectifier.

In some embodiments, the wireless power receiver includes an auxiliary matching network coupled to and positioned between the antenna and the auxiliary rectifier. Furthermore, adjusting the load of the auxiliary rectifier can cause a mismatch of the auxiliary matching network, which results the portion of the RF signals being reflected by the antenna. Moreover, the wireless power receiver may also include a toggle coupled to a load-adjusting mechanism (e.g., a portion of the circuit may be connected by a switch when then toggle is in one state, and disconnected when the toggle is in another state, which can change the impedance of the circuit, see also FIG. 6C illustrating three different types of mechanisms for adjusting the load), and the load-adjusting mechanism is coupled to the auxiliary rectifier (e.g., the adjustable loads components shown in FIG. 6C). Furthermore, toggling the switch (e.g., switch 602 as shown in FIG. 6C) causes a change within the load-adjusting mechanism that produces a change in the load of the receiver, which results in the impedance mismatch between the wireless power receiver and the wireless power transmitter. In some embodiments, adjusting the load of the auxiliary rectifier is done by coupling an output of the auxiliary rectifier to a load adjusting mechanism, in parallel, to (i) a capacitor, which is coupled to a ground, and (ii) a first resistor, where the first resistor is coupled, in parallel, to a second resistor in series, which is coupled to a ground, and a tapped switch coupled to the output of the first resistor in series, and a ground. The tapped switch is coupled to a toggle for opening and closing the tapped switch. In some embodiments, the load adjusting mechanism comprises (i) a capacitor, which is coupled to a ground, (ii) a first resistor, and (iii) a second resistor, where the second resistor is coupled to a series switch, which is coupled to a ground. The series switch is coupled to a toggle for opening and closing the series switch. In some embodiments, adjusting the load of the auxiliary rectifier is done by coupling the output of the auxiliary rectifier, in parallel, to (i) a capacitor, which is coupled to a ground, (ii) a variable resistor, which is coupled to a ground. The variable resistor is coupled to a toggle for adjusting the resistance of the variable resistor.

In some embodiments, in response to the wireless power receiver sending the modulated signal, the wireless power transmitter may interpret the modulated signal as an instruction to cease sending the RF signals to the wireless power receiver. In some other embodiments, in response to the wireless power receiver sending the modulated signal, the wireless power transmitter may interpret the modulated signal as an instruction to adjust transmission characteristics of the RF signals to the wireless power receiver (e.g., increase or decrease a power of the RF signals, among other adjustments). In some embodiments, the adjustment is dynamic and depends on the capabilities of the transmitter to handle reflected signals.

In some embodiments, after introducing the impedance mismatch and while continuing to receive the RF signals from the wireless power transmitter, the method further includes matching (710) the impedance between the wireless power receiver and the wireless power transmitter, which stops reflection of the portion of the RF signals by the antenna. In some embodiments, the wireless power transmitter ceases to transmit the RF signals to the wireless power receiver in response to receiving the modulated signal from the wireless power receiver. In some embodiments, in response to the wireless power receiver sending the modulated signal, the transmitter determines that a threshold amount of the reflected signal indicates that the receiver no longer requires RF signals, and as a result the wireless power transmitter stops transmitting RF signals to the wireless power receiver. In some embodiments, when a certain percentage is reflected back from the wireless power receiver, but does not exceed a threshold to stop sending power, the wireless power transmitter can adjust the amount of RF signals it is sending to the wireless power receiver.

In light of the principles discussed above, the following embodiments relate to converting energy from the received RF signals into an alternating current.

In some embodiments, a wireless power receiver is provided that comprises: a wireless-power-receiving antenna configured to receive radio frequency (RF) power signals, and convert energy from the received RF signals into an alternating current. In some embodiments, the coupler can be coupled to an output of a first capacitor, and the capacitors input is coupled to the antenna. In some embodiments, the coupler can be coupled to the output of a series of capacitors that are coupled to the antenna. In some embodiments, the coupler can be coupled to the output of the primary rectifier. In some embodiments, the coupler can be coupled after a series of capacitors. In such an embodiment, the capacitors are used to isolate the coupling point. In some embodiments, the coupler can be coupled to the output of a matching network, or the output of a series of matching networks. In some embodiments, a wireless power receiver comprises a primary rectifier configured to: (i) receive a first portion of the alternating current, and (ii) rectify the first portion of the alternating current into primary direct current having a first voltage and a first power level, the primary direct current used to provide power or charge to an electronic device. In some embodiments, the primary rectifier is coupled to a capacitor to reduce ripple (e.g., remove the variations in direct current). In some embodiments the RF coupler is not used, and the antenna is directly coupled (e.g., a diode) to the primary rectifier and the secondary rectifier. In such an embodiment, an input matching network may be placed between the antenna and the diode. In some embodiments, a wireless power receiver comprises a secondary rectifier configured to: (i) receive a second portion of the alternating current, and (ii) rectify the second portion of the alternating current into a secondary direct current having a second voltage and a second power level. In some embodiments, the direct current flows to a capacitor, and then flows to the ground. In some embodiments, the second power level of the secondary direct current is less than the first power level of the primary direct current. In some embodiments, the magnitude of the secondary direct current is a small amount of the received RF signals, either represented by a decibel value or a percentage of the incoming RF signals. For example, the power (i.e., voltage, or current) sent to the secondary rectifier can be −30 dB to −40 dB, or roughly less than 1% of the RF signals.

In some embodiments, the wireless power receiver's second voltage of the secondary direct current indicates whether the antenna is receiving RF signals from a wireless-power-transmitting device. In some embodiments, the magnitude of the secondary direct current can indicate that the secondary direct current is a minimum current necessary to indicate that the antenna is receiving the RF signals from the wireless-power-transmitting device, where the magnitude corresponds to a value of approximately −30 dB to −40 dB, or roughly 1% of the alternating current, or a voltage level of 1 volt to 40 volts. In some embodiments, the magnitude of the secondary direct current can be measured at multiple measurement points (e.g., at VAUX 409-1 and VAUX_DIV 409-2 in FIGS. 4A and 4E), and an amount of voltage detected at each of the measurement points can be controlled by using one or more resistors (fixed and/or variable). For example, as shown in FIGS. 4A and 4E, a voltage detected at VAUX can be stepped down by using two in-series resistors, labelled as numerals 407 and 408. These measurement points (e.g., at VAUX 409-1 and VAUX_DIV 409-2 in FIGS. 4A and 4E) may be set depending on the type of detection mechanism. A few example detection mechanisms are: digital logic detection mechanism, voltage comparator detection mechanism, and/or an analog to direct current converter (ADC) detection mechanism.

When using a digital logic as a detection mechanism, the threshold voltage is set to half of the digital logic supply voltage (i.e. when supply voltage of digital logic is 5 volts, the logic threshold voltage can be set to be 2.5 volts). When the input is higher than the logic threshold voltage, the digital logic can output a “low” state that indicates that the input is lower than the logic threshold voltage. When the input voltage is lower than the logic threshold voltage, the digital logic can output a “high” state that indicates that the input is higher than the logic threshold voltage.

When using a voltage comparator as a detection mechanism, the threshold voltage can be set to any desired voltage within the supply range by using a voltage generator (i.e. the threshold voltage can be set to any value within supply voltage of the voltage comparator). When the input voltage is higher than the desired threshold voltage, the voltage comparator can output a “low” state that indicates that the input is lower than the desired threshold voltage. When the input voltage is lower than the desired threshold voltage, the voltage comparator can output a “high” state indicating that the input voltage is higher than desired threshold voltage.

When using analog to direct current converter (ADC), the threshold can be set arbitrarily using an external reference voltage. The ADC also digitizes the analog voltage value, which is used to tell how far apart the input voltage is from desired threshold (reference) voltage.

In some embodiments, the wireless power receiver includes an RF coupler that is coupled to the antenna, the RF coupler comprises distinct first and second outputs, and the primary rectifier is coupled to the first output of the RF coupler, while the secondary rectifier is coupled to the second output of the RF coupler.

In some embodiments, the wireless power receiver comprises at least one impedance matching network positioned between and coupled to the first output of the RF coupler and the secondary rectifier. In some embodiments, a series of matching networks may be implemented, as shown as 403-n in FIGS. 4B, 5B, and 6B. In some embodiments, the at least one matching network is configured to match an impedance of a source (e.g., a transmitter) of the RF signals.

In some embodiments, the wireless power receiver comprises at least one impedance matching network positioned between and coupled to an input of the RF coupler and the antenna, wherein the at least one matching network is configured to match an impedance of a source of the RF signals. In some embodiments, the wireless power receiver further comprises one or more additional electrical components (e.g., the one or more additional electrical components are capacitor 404, and ZL 406, which represent the charging components the receiver is coupled to, as shown in FIGS. 4A, 4B, 4E, 6A, and 6B) that are used to deliver the primary direct current that is used to power or charge to the electronic device; and a controller configured to: detect that the second voltage of the secondary direct current satisfies one or more power-detection thresholds that indicate that the antenna is receiving RF signals from a wireless-power-transmitting device; and in response to detecting that the second direct current satisfies the one or more power-detection thresholds, send a signal that causes each of the one or more additional electrical components to prepare for receiving the primary direct current. In some embodiments the power-detection threshold is met when: (i) the voltage meets a value that corresponds to a received amount of the RF power signals (e.g., −40 dB to −1 dB), (ii) the voltage meets a value that corresponds to a percentage of the RF power signals (e.g., 0.001% to 2%), or (iii) the voltage is within a specified range (e.g., 1 volt to 40 volts, 5 volts to 30 volts, 5 volts to 10 volts).

In some embodiments, the one or more power-detection thresholds are satisfied when the second voltage of the secondary direct current is in a range of approximately 5 volts to 30 volts.

In some embodiments, detecting that the second voltage of the secondary direct current satisfies one or more power-detection thresholds is performed by comparing the second voltage to a respective power-detection threshold of the one or more power-detection thresholds at a first measurement point, a second measurement point, or both the first and second measurement points.

In some embodiments, the wireless power receiver comprises a first measurement point that is located before a voltage divider that is configured to step down the second voltage, and the second measurement point is located after the voltage divider. In some embodiments, variable resistors are used to adjust the resistance, and consequently adjust the voltage step down.

In some embodiments, the second portion of the alternating current is approximately 0.01% to 0.1% of the alternating current. And, in other embodiments, this range can be expanded or retracted, e.g., so that the range is from approximately 0.001% to 10%. In some other embodiments, the second portion of the alternating current range is expanded to cover approximately less than 1% of the alternating current. In some embodiments, the wireless power receiver comprises: (i) a first storage component (e.g., a first capacitor, or a battery) and (ii) a second storage component (e.g., a first capacitor, or a battery) having a lower storage capacity than the first storage component (e.g., a first capacitor, or a battery); the first storage component (e.g., a first capacitor, or a battery) is coupled to an output of the primary rectifier; the second storage component (e.g., a first capacitor, or a battery) is coupled to an output of the secondary rectifier; the second storage component (e.g., a first capacitor, or a battery), due to its lower storage capacity, is configured to discharge faster than the first storage component (e.g., a first capacitor, or a battery), wherein discharge of the second storage component (e.g., a first capacitor, or a battery) indicates to the wireless power receiver that RF signals are no longer being received at the antenna, and to prepare components of the wireless power receiver for shutdown.

In some embodiments, the secondary rectifier that is composed of: (i) an input configured to receive the second portion of the alternating current, (ii) a first diode, and (iii) a second diode, and the input of the secondary rectifier is coupled to: a cathode of a first diode, wherein an anode of the first diode is coupled to a ground; and an anode of a second diode, wherein a cathode of the second diode is coupled to an output of the secondary rectifier. Although, this embodiment includes these components, it should be understood that other embodiments include these components in addition to other components.

In some embodiments, the secondary rectifier is composed of: (i) an input configured to receive the second portion of the alternating current, (ii) a first diode-connected transistor, and (iii) a second diode-connected transistor, and the input of the secondary rectifier is coupled to: (i) a first diode-connected transistor, wherein the first diode-connected transistor is connected to a ground; and (ii) a second diode-connected transistor, wherein the second diode-connected transistor is connected to an output of the secondary rectifier. Although, this embodiment includes these components, it should be understood that other embodiments include these components in addition to other components.

In some embodiments, the RF coupler is a directional coupler. In some embodiments, a directional coupler is a first path (e.g., a primary RF path) that is coupled to an antenna configured to receive RF signals and convert them to alternating current, and a second path (e.g., a secondary RF path) that is not coupled, but placed in parallel with the first path. In such an embodiment, the second path can be coupled to a resistor that is coupled to a ground.

In some embodiments, the RF coupler is a capacitive coupler. In some embodiments, a capacitive coupler includes an antenna coupled in parallel with a first capacitor, and a first path (e.g., a primary RF path). In such an embodiment, the first capacitor is coupled in parallel to a second capacitor, and a second path (e.g., a secondary RF path). In such embodiments, the second capacitor can be coupled to a ground.

In some embodiments, the RF coupler is a resistive coupler. In some embodiments, a resistive coupler includes an antenna coupled in parallel with a first resistor, and a first path (e.g., a primary RF path). In such an embodiment, the first resistor is coupled in parallel to a second resistor, and a second path (e.g., a secondary RF path). In such embodiments, the second resistor can be coupled to a ground.

In yet another aspect, the discussion below relates to power surge protection for a wireless power receiver. A method of power surge protection for a wireless power receiver, occurs at a wireless power receiver comprising: (i) an antenna, (ii) a rectifier coupled to the antenna, and (iii) a switch coupled to the rectifier, the switch configured to create an impedance mismatch or match before an input of the rectifier. While the switch is in a default-closed state that grounds the switch and creates an impedance mismatch before an input of the rectifier: receiving, by the antenna of the wireless power receiver, radio frequency (RF) signals as an alternating current, wherein a first portion of the alternating current is reflected away from the input of the rectifier due to the impedance mismatch, and a second portion of the alternating current flows through the switch and to ground; and while the switch is in an open state that creates an impedance match at the input of the rectifier: the first portion of the alternating current flows through the input of the rectifier, allowing the first portion of the alternating current to be converted into direct current that is used to charge or power an electronic device; and the second portion of the alternating current flows through the switch and to the input of the rectifier, allowing the second portion of the alternating current to be converted into direct current that is used to charge or power an electronic device. In this way, a switch can be employed to protect a sensitive component (e.g., rectifier) in a wireless-power-receiving circuit from initial surges of RF energy that may otherwise damage that sensitive component. In some embodiments, a capacitor may be placed between the antenna and the coupling mechanism. In some embodiments, an output of the rectifier is coupled to a capacitor that is coupled to a ground, which reduces ripple from the conversion of RF signals to direct current (DC) signals.

In some embodiments, a negative voltage generator is placed before the switch. In some embodiments, the negative voltage generator (i.e., a rectifier) rectifies RF signals to negative voltage, which causes the switch to enter an opened state by reaching a zero volt threshold.

In some embodiments, the switch transitions from the default-closed state to the open state gradually over a period of time, and during the period of time, a part of the first portion of the alternating current continues to be reflected away from the input of the rectifier. In some embodiments, over this period of time, the impedance mismatch gradually decreases, until the mismatch is substantially removed (e.g., less than 5% of the mismatch remains). In some embodiments, the period of time is determined by the specifications of the switch. In some embodiments, the switch may be a GaN switch or a depletion mode metal oxide semiconductor (MOS) switch that is designed to open after a set period of time. In some embodiments, the period of time can be dynamically adjusted based on a detected voltage of the alternating current.

In some embodiments, dynamically adjusting includes reducing the period of time based on a determination that the detected voltage does not satisfy (e.g., less than or equal to) a defined threshold value (e.g., the defined threshold can be between 4-10 volts, or another appropriate value that is slightly above a voltage used to charge a power source of the electronic device coupled to the wireless power receiver).

In some embodiments, dynamically adjusting includes increasing the period of time based on a determination that the detected voltage satisfies (e.g., is greater than) a defined threshold value.

In some embodiments, the switch transitions from default-closed to open state by using a Gallium Nitride (GaN) switch or a depletion mode metal oxide semiconductor (MOS) switch. In some embodiments, the switch has a voltage threshold that is met before it enters the open fully open. In some embodiments, the voltage threshold is zero volts.

In some embodiments, while the switch is in the open state: ceasing to receive the RF signals by the antenna of the wireless power receiver. The ceasing to receive the RF signals causes the switch to transition back to the default-closed state from the open state (e.g., when the voltage falls below a threshold voltages for the switch, as a result of no longer receiving the RF signals} {In some embodiments, the switch changes to the normally closed state when the voltage falls below a zero volt threshold).

In some embodiments, the wireless power receiver includes a coupling mechanism that is coupled to the antenna, wherein the coupling mechanism includes a first output and a second output, and further wherein: the first output of the coupling mechanism is coupled to the rectifier; and the second output of the coupling mechanism is coupled to the switch.

In some embodiments, the coupling mechanism partitions the alternating current, wherein the coupling mechanism: directs a first portion of the alternating current to the first output of the coupling mechanism; and directs a second portion of the alternating current to the second output of the coupling mechanism.

In some embodiments, the switch is coupled to an output of the rectifier. In some embodiments, the wireless power receiver further comprises a matching network having (i) an input coupled to the first output of the coupling mechanism and (ii) an output coupled to the rectifier. In some embodiments, more than one matching network may be utilized to match the impedance of the system to the source.

In some embodiments, the switch is coupled to the matching network and the rectifier. In some embodiments, the switch can be coupled to the output of a plurality of matching networks in a series.

Although some of various drawings illustrate a number of logical stages in a particular order, stages which are not order dependent may be reordered and other stages may be combined or broken out. While some reordering or other groupings are specifically mentioned, others will be obvious to those of ordinary skill in the art, so the ordering and groupings presented herein are not an exhaustive list of alternatives. Moreover, it should be recognized that the stages could be implemented in hardware, firmware, software, or any combination thereof.

The foregoing description, for purpose of explanation, has been described with reference to specific embodiments. However, the illustrative discussions above are not intended to be exhaustive or to limit the scope of the claims to the precise forms disclosed. Many modifications and variations are possible in view of the above teachings. The embodiments were chosen in order to best explain the principles underlying the claims and their practical applications, to thereby enable others skilled in the art to best use the embodiments with various modifications as are suited to the particular uses contemplated.

Claims

1. A method of power surge protection for a wireless-power receiver, the method comprising:

at a wireless-power receiver comprising: (i) an antenna, (ii) a rectifier coupled to the antenna, and (iii) a depletion-mode switch coupled to the rectifier, the depletion-mode switch being configured to create an impedance mismatch or an impedance match between the rectifier and the antenna: while the depletion-mode switch is in a default-closed state that creates the impedance mismatch between the rectifier and the antenna: receiving, by the antenna of the wireless-power receiver, radio frequency (RF) signals as an alternating current from a wireless power transmitter, wherein a first amount of the alternating current is reflected away from an input of the rectifier due to the impedance mismatch; while the impedance mismatch is present, providing a second amount of the alternating current to the depletion-mode switch to cause the depletion-mode switch to begin transitioning to an open state that creates the impedance match between the rectifier and the antenna; and while the depletion-mode switch is in the open state that creates the impedance match between the rectifier and the antenna: receiving, by the antenna of the wireless-power receiver, additional RF signals as an additional alternating current from the wireless power transmitter, wherein the additional alternating current flows through the input of the rectifier to be converted into direct current that is used to charge or power an electronic device.

2. The method of claim 1 wherein a negative voltage generator is placed to drive the depletion-mode switch to transition from the default-closed state to the open state.

3. The method of claim 1, wherein the depletion-mode switch transitions from the default-closed state to the open state gradually over a period of time, and during the period of time, a part of the first amount of the alternating current continues to be reflected away from the input of the rectifier.

4. The method of claim 1, wherein the depletion-mode switch is a Gallium Nitride (GaN) switch or a metal oxide semiconductor (MOS) switch.

5. The method of claim 1, wherein a period of time is required for the depletion-mode switch to transition to the open state, and the method further comprises, dynamically adjusting the period of time based on a detected voltage of the alternating current.

6. The method of claim 5, wherein dynamically adjusting the period of time includes reducing the period of time based on a determination that the detected voltage does not satisfy a defined threshold value.

7. The method of claim 5, wherein dynamically adjusting the period of time includes increasing the period of time based on a determination that the detected voltage satisfies a defined threshold value.

8. The method of claim 1, wherein the depletion-mode switch has a voltage threshold that is met before it enters the open state.

9. The method of claim 8, wherein the voltage threshold is zero volts.

10. The method of claim 1, further comprising, while the depletion-mode switch is in the open state:

ceasing to receive the RF signals by the antenna of the wireless-power receiver,
wherein ceasing to receive the RF signals causes the depletion-mode switch to transition back to the default-closed state from the open state.

11. The method of claim 1, wherein:

the wireless-power receiver includes a coupling mechanism that is coupled to the antenna;
the coupling mechanism includes a first output and a second output;
the first output of the coupling mechanism is coupled to the rectifier; and
the second output of the coupling mechanism is coupled to the depletion-mode switch.

12. The method of claim 11, wherein the depletion-mode switch is coupled to an output of a second rectifier.

13. A system for power surge protection for a wireless-power receiver, comprising:

an antenna;
a rectifier coupled to the antenna;
a depletion-mode switch coupled to the rectifier, the depletion-mode switch being configured to create an impedance mismatch or an impedance match between the rectifier and the antenna;
one or more processors; and
memory storing one or more programs for execution by the one or more processors, the one or more programs including instructions for: while the depletion-mode switch is in a default-closed state that creates an impedance mismatch between the rectifier and the antenna: receiving, by the antenna of the wireless-power receiver, radio frequency (RF) signals as an alternating current from a wireless power transmitter, wherein a first amount of the alternating current is reflected away from an input of the rectifier due to the impedance mismatch; while the impedance mismatch is present, providing a second amount of the alternating current to the depletion-mode switch to cause the depletion-mode switch to begin transitioning to an open state that creates the impedance match between the rectifier and the antenna; and while the depletion-mode switch is in the open state that creates the impedance match between the rectifier and the antenna: receiving, by the antenna of the wireless-power receiver, additional RF signals as an additional alternating current from the wireless power transmitter, wherein the additional alternating current flows through the input of the rectifier to be converted into direct current that is used to charge or power an electronic device.

14. The system of claim 13, further comprising a negative voltage generator configured to drive the depletion-mode switch to transition from the default-closed state to the open state.

15. The system of claim 13, wherein the depletion-mode switch is configured to transition from the default-closed state to the open state gradually over a period of time, and during the period of time, a part of the first amount of the alternating current continues to be reflected away from the input of the rectifier.

16. The system of claim 13, wherein a period of time is required for the depletion- mode switch to transition to the open state, and the period of time is configured to be dynamically adjusted based on a detected voltage of the alternating current.

17. The system of claim 13, wherein:

the depletion-mode switch has a voltage threshold that is met before it enters the open state; and
the voltage threshold is zero volts.

18. The system of claim 13, further comprising, while the depletion-mode switch is in the open state, the system is configured to:

cease receiving RF signals by the antenna of the wireless-power receiver,
wherein ceasing to receive the RF signals causes the depletion-mode switch to transition back to the default-closed state from the open state.

19. The system of claim 13, wherein the depletion-mode switch is coupled to an output of a second rectifier.

20. A non-transitory computer-readable storage medium storing one or more programs, the one or more programs comprising instructions, that when executed by a system with an antenna of a wireless-power receiver, a rectifier coupled to the antenna, and a depletion-mode switch coupled to the rectifier, the depletion-mode switch being configured to create an impedance mismatch or an impedance match between the rectifier and the antenna, cause the system to:

while the depletion-mode switch is in a default-closed state that creates an impedance mismatch between the rectifier and the antenna: receive, by the antenna of the wireless-power receiver, radio frequency (RF) signals as an alternating current from a wireless power transmitter, wherein a first amount of the alternating current is reflected away from an input of the rectifier due to the impedance mismatch;
while the impedance mismatch is present, provide a second amount of the alternating current to the depletion-mode switch to cause the depletion-mode switch to begin transitioning to an open state that creates the impedance match between the rectifier and the antenna; and
while the depletion-mode switch is in the open state that creates the impedance match between the rectifier and the antenna: receive, by the antenna of the wireless-power receiver, additional RF signals as an additional alternating current from the wireless power transmitter, wherein the additional alternating current flows through the input of the rectifier to be converted into direct current that is used to charge or power an electronic device.

21. The non-transitory computer-readable storage medium of claim 20, wherein the system that executes the instructions stored on the non-transitory computer-readable storage medium further comprises a negative voltage generator configured to drive the depletion-mode switch to transition from the default-closed state to the open state.

22. The non-transitory computer-readable storage medium of claim 20, wherein the depletion-mode switch is configured to transition from the default-closed state to the open state gradually over a period of time, and during the period of time, a part of the first amount of the alternating current continues to be reflected away from the input of the rectifier.

23. The non-transitory computer-readable storage medium of claim 20, wherein a period of time is required for the depletion-mode switch to transition to the open state, and the period of time is configured to be dynamically adjusted based on a detected voltage of the alternating current.

24. The non-transitory computer-readable storage medium of claim 20, wherein:

the depletion-mode switch has a voltage threshold that is met before it enters the open state; and
the voltage threshold is zero volts.

25. The non-transitory computer-readable storage medium of claim 20, further comprising instructions that, when executed by the system, cause the system to:

while the depletion-mode switch is in the open state, cease receiving RF signals by the antenna of the wireless-power receiver,
wherein ceasing to receive the RF signals causes the depletion-mode switch to transition back to the default-closed state from the open state.

26. The non-transitory computer-readable storage medium of claim 20, wherein the depletion-mode switch is coupled to an output of a second rectifier.

Referenced Cited
U.S. Patent Documents
787412 April 1905 Tesla
2811624 October 1957 Haagensen
2863148 December 1958 Gammon et al.
3167775 January 1965 Guertler
3434678 March 1969 Brown et al.
3696384 October 1972 Lester
3754269 August 1973 Clavin
4101895 July 18, 1978 Jones, Jr.
4360741 November 23, 1982 Fitzsimmons et al.
4944036 July 24, 1990 Hyatt
4995010 February 19, 1991 Knight
5142292 August 25, 1992 Chang
5200759 April 6, 1993 McGinnis
5211471 May 18, 1993 Rohrs
5276455 January 4, 1994 Fitzsimmons et al.
5548292 August 20, 1996 Hirshfield et al.
5556749 September 17, 1996 Mitsuhashi et al.
5568088 October 22, 1996 Dent et al.
5631572 May 20, 1997 Sheen et al.
5646633 July 8, 1997 Dahlberg
5697063 December 9, 1997 Kishigami et al.
5712642 January 27, 1998 Hulderman
5936527 August 10, 1999 Isaacman et al.
5982139 November 9, 1999 Parise
6046708 April 4, 2000 MacDonald, Jr. et al.
6061025 May 9, 2000 Jackson et al.
6127799 October 3, 2000 Krishnan
6127942 October 3, 2000 Welle
6163296 December 19, 2000 Lier et al.
6176433 January 23, 2001 Uesaka et al.
6271799 August 7, 2001 Rief
6289237 September 11, 2001 Mickle et al.
6329908 December 11, 2001 Frecska
6400586 June 4, 2002 Raddi et al.
6421235 July 16, 2002 Ditzik
6437685 August 20, 2002 Hanaki
6456253 September 24, 2002 Rummeli et al.
6476795 November 5, 2002 Derocher et al.
6501414 December 31, 2002 Amdt et al.
6583723 June 24, 2003 Watanabe et al.
6597897 July 22, 2003 Tang
6615074 September 2, 2003 Mickle et al.
6650376 November 18, 2003 Obitsu
6664920 December 16, 2003 Mott et al.
6680700 January 20, 2004 Hilgers
6798716 September 28, 2004 Charych
6803744 October 12, 2004 Sabo
6853197 February 8, 2005 McFarland
6856291 February 15, 2005 Mickle et al.
6911945 June 28, 2005 Korva
6960968 November 1, 2005 Odendaal et al.
6967462 November 22, 2005 Landis
6988026 January 17, 2006 Breed et al.
7003350 February 21, 2006 Denker et al.
7012572 March 14, 2006 Schaffner et al.
7027311 April 11, 2006 Vanderelli et al.
7068234 June 27, 2006 Sievenpiper
7068991 June 27, 2006 Parise
7079079 July 18, 2006 Jo et al.
7183748 February 27, 2007 Unno et al.
7191013 March 13, 2007 Miranda et al.
7193644 March 20, 2007 Carter
7196663 March 27, 2007 Bolzer et al.
7205749 April 17, 2007 Hagen et al.
7215296 May 8, 2007 Abramov et al.
7222356 May 22, 2007 Yonezawa et al.
7274334 September 25, 2007 O'Riordan et al.
7274336 September 25, 2007 Carson
7351975 April 1, 2008 Brady et al.
7359730 April 15, 2008 Dennis et al.
7372408 May 13, 2008 Gaucher
7392068 June 24, 2008 Dayan
7403803 July 22, 2008 Mickle et al.
7443057 October 28, 2008 Nunally
7451839 November 18, 2008 Perlman
7463201 December 9, 2008 Chiang et al.
7471247 December 30, 2008 Saily
7535195 May 19, 2009 Horovitz et al.
7614556 November 10, 2009 Overhultz et al.
7639994 December 29, 2009 Greene et al.
7643312 January 5, 2010 Vanderelli et al.
7652577 January 26, 2010 Madhow et al.
7679576 March 16, 2010 Riedel et al.
7702771 April 20, 2010 Ewing et al.
7786419 August 31, 2010 Hyde et al.
7812771 October 12, 2010 Greene et al.
7830312 November 9, 2010 Choudhury et al.
7844306 November 30, 2010 Shearer et al.
7868482 January 11, 2011 Greene et al.
7898105 March 1, 2011 Greene et al.
7904117 March 8, 2011 Doan et al.
7911386 March 22, 2011 Ito et al.
7925308 April 12, 2011 Greene et al.
7948208 May 24, 2011 Partovi et al.
8049676 November 1, 2011 Yoon et al.
8055003 November 8, 2011 Mittleman et al.
8070595 December 6, 2011 Alderucci et al.
8072380 December 6, 2011 Crouch
8092301 January 10, 2012 Alderucci et al.
8099140 January 17, 2012 Arai
8115448 February 14, 2012 John
8159090 April 17, 2012 Greene et al.
8159364 April 17, 2012 Zeine
8180286 May 15, 2012 Yamasuge
8184454 May 22, 2012 Mao
8228194 July 24, 2012 Mickle
8234509 July 31, 2012 Gioscia et al.
8264101 September 11, 2012 Hyde et al.
8264291 September 11, 2012 Morita
8276325 October 2, 2012 Clifton et al.
8278784 October 2, 2012 Cook et al.
8284101 October 9, 2012 Fusco
8310201 November 13, 2012 Wright
8338991 December 25, 2012 Von Novak et al.
8362745 January 29, 2013 Tinaphong
8380255 February 19, 2013 Shearer et al.
8384600 February 26, 2013 Huang et al.
8410953 April 2, 2013 Zeine
8411963 April 2, 2013 Luff
8432062 April 30, 2013 Greene et al.
8432071 April 30, 2013 Huang et al.
8446248 May 21, 2013 Zeine
8447234 May 21, 2013 Cook et al.
8451189 May 28, 2013 Fluhler
8452235 May 28, 2013 Kirby et al.
8457656 June 4, 2013 Perkins et al.
8461817 June 11, 2013 Martin et al.
8467733 June 18, 2013 Leabman
8497601 July 30, 2013 Hall et al.
8497658 July 30, 2013 Von Novak et al.
8552597 October 8, 2013 Song et al.
8558661 October 15, 2013 Zeine
8560026 October 15, 2013 Chanterac
8564485 October 22, 2013 Milosavljevic et al.
8604746 December 10, 2013 Lee
8614643 December 24, 2013 Leabman
8621245 December 31, 2013 Shearer et al.
8626249 January 7, 2014 Kuusilinna et al.
8629576 January 14, 2014 Levine
8653966 February 18, 2014 Rao et al.
8655272 February 18, 2014 Saunamaki
8674551 March 18, 2014 Low et al.
8686685 April 1, 2014 Moshfeghi
8686905 April 1, 2014 Shtrom
8712355 April 29, 2014 Black et al.
8712485 April 29, 2014 Tam
8718773 May 6, 2014 Wills et al.
8729737 May 20, 2014 Schatz et al.
8736228 May 27, 2014 Freed et al.
8760113 June 24, 2014 Keating
8770482 July 8, 2014 Ackermann et al.
8772960 July 8, 2014 Yoshida
8823319 September 2, 2014 Von Novak, III et al.
8832646 September 9, 2014 Wendling
8854176 October 7, 2014 Zeine
8860364 October 14, 2014 Low et al.
8897770 November 25, 2014 Frolov et al.
8903456 December 2, 2014 Chu et al.
8917057 December 23, 2014 Hui
8923189 December 30, 2014 Leabman
8928544 January 6, 2015 Massie et al.
8937408 January 20, 2015 Ganem et al.
8946940 February 3, 2015 Kim et al.
8963486 February 24, 2015 Kirby et al.
8970070 March 3, 2015 Sada et al.
8989053 March 24, 2015 Skaaksrud et al.
9000616 April 7, 2015 Greene et al.
9001622 April 7, 2015 Perry
9006934 April 14, 2015 Kozakai et al.
9021277 April 28, 2015 Shearer et al.
9030161 May 12, 2015 Lu et al.
9059598 June 16, 2015 Kang et al.
9059599 June 16, 2015 Won et al.
9077188 July 7, 2015 Moshfeghi
9083595 July 14, 2015 Rakib et al.
9088216 July 21, 2015 Garrity et al.
9124125 September 1, 2015 Leabman et al.
9130397 September 8, 2015 Leabman et al.
9130602 September 8, 2015 Cook
9142998 September 22, 2015 Yu et al.
9143000 September 22, 2015 Leabman et al.
9143010 September 22, 2015 Urano
9153074 October 6, 2015 Zhou et al.
9178389 November 3, 2015 Hwang
9225196 December 29, 2015 Huang et al.
9240469 January 19, 2016 Sun et al.
9242411 January 26, 2016 Kritchman et al.
9244500 January 26, 2016 Cain et al.
9252628 February 2, 2016 Leabman et al.
9270344 February 23, 2016 Rosenberg
9276329 March 1, 2016 Jones et al.
9282582 March 8, 2016 Dunsbergen et al.
9294840 March 22, 2016 Anderson et al.
9297896 March 29, 2016 Andrews
9318898 April 19, 2016 John
9368020 June 14, 2016 Bell et al.
9401977 July 26, 2016 Gaw
9409490 August 9, 2016 Kawashima
9419335 August 16, 2016 Pintos
9419443 August 16, 2016 Leabman
9438045 September 6, 2016 Leabman
9438046 September 6, 2016 Leabman
9444283 September 13, 2016 Son et al.
9450449 September 20, 2016 Leabman et al.
9461502 October 4, 2016 Lee et al.
9520725 December 13, 2016 Masaoka et al.
9520748 December 13, 2016 Hyde et al.
9522270 December 20, 2016 Perryman et al.
9532748 January 3, 2017 Denison et al.
9537354 January 3, 2017 Bell et al.
9537357 January 3, 2017 Leabman
9537358 January 3, 2017 Leabman
9538382 January 3, 2017 Bell et al.
9544640 January 10, 2017 Lau
9559553 January 31, 2017 Bae
9564773 February 7, 2017 Pogorelik et al.
9571974 February 14, 2017 Choi et al.
9590317 March 7, 2017 Zimmerman et al.
9590444 March 7, 2017 Walley
9620996 April 11, 2017 Zeine
9647328 May 9, 2017 Dobric
9706137 July 11, 2017 Scanlon et al.
9711999 July 18, 2017 Hietala et al.
9723635 August 1, 2017 Nambord et al.
9793758 October 17, 2017 Leabman
9793764 October 17, 2017 Perry
9800080 October 24, 2017 Leabman et al.
9800172 October 24, 2017 Leabman
9806564 October 31, 2017 Leabman
9819230 November 14, 2017 Petras et al.
9824815 November 21, 2017 Leabman et al.
9825674 November 21, 2017 Leabman
9831718 November 28, 2017 Leabman et al.
9838083 December 5, 2017 Bell et al.
9843213 December 12, 2017 Leabman et al.
9843229 December 12, 2017 Leabman
9843763 December 12, 2017 Leabman et al.
9847669 December 19, 2017 Leabman
9847677 December 19, 2017 Leabman
9847679 December 19, 2017 Bell et al.
9853361 December 26, 2017 Chen et al.
9853692 December 26, 2017 Bell et al.
9859756 January 2, 2018 Leabman et al.
9859758 January 2, 2018 Leabman
9866279 January 9, 2018 Bell et al.
9867032 January 9, 2018 Verma et al.
9871301 January 16, 2018 Contopanagos
9876380 January 23, 2018 Leabman et al.
9876394 January 23, 2018 Leabman
9876536 January 23, 2018 Bell et al.
9876648 January 23, 2018 Bell
9882394 January 30, 2018 Bell et al.
9882427 January 30, 2018 Leabman et al.
9887584 February 6, 2018 Bell et al.
9887739 February 6, 2018 Leabman et al.
9891669 February 13, 2018 Bell
9893554 February 13, 2018 Bell et al.
9893555 February 13, 2018 Leabman et al.
9893564 February 13, 2018 de Rochemont
9899744 February 20, 2018 Contopanagos et al.
9899844 February 20, 2018 Bell et al.
9899861 February 20, 2018 Leabman et al.
9899873 February 20, 2018 Bell et al.
9912199 March 6, 2018 Leabman et al.
9916485 March 13, 2018 Lilly et al.
9917477 March 13, 2018 Bell et al.
9923386 March 20, 2018 Leabman et al.
9939864 April 10, 2018 Bell et al.
9941747 April 10, 2018 Bell et al.
9965009 May 8, 2018 Bell et al.
9966765 May 8, 2018 Leabman
9966784 May 8, 2018 Leabman
9967743 May 8, 2018 Bell et al.
9973008 May 15, 2018 Leabman
10003211 June 19, 2018 Leabman et al.
10008777 June 26, 2018 Broyde et al.
10008889 June 26, 2018 Bell et al.
10014728 July 3, 2018 Leabman
10027159 July 17, 2018 Hosseini
10038337 July 31, 2018 Leabman et al.
10050462 August 14, 2018 Leabman et al.
10056782 August 21, 2018 Leabman
10063064 August 28, 2018 Bell et al.
10063105 August 28, 2018 Leabman
10063106 August 28, 2018 Bell et al.
10068703 September 4, 2018 Contopanagos
10075008 September 11, 2018 Bell et al.
10079515 September 18, 2018 Hosseini et al.
10090699 October 2, 2018 Leabman
10090714 October 2, 2018 Bohn et al.
10090886 October 2, 2018 Bell et al.
10103552 October 16, 2018 Leabman et al.
10103582 October 16, 2018 Leabman et al.
10110046 October 23, 2018 Esquibel et al.
10122219 November 6, 2018 Hosseini et al.
10122415 November 6, 2018 Bell et al.
10124754 November 13, 2018 Leabman
10128686 November 13, 2018 Leabman et al.
10128695 November 13, 2018 Leabman et al.
10128699 November 13, 2018 Leabman
10134260 November 20, 2018 Bell et al.
10135112 November 20, 2018 Hosseini
10135294 November 20, 2018 Leabman
10135295 November 20, 2018 Leabman
10141768 November 27, 2018 Leabman et al.
10141771 November 27, 2018 Hosseini et al.
10141791 November 27, 2018 Bell et al.
10148097 December 4, 2018 Leabman et al.
10153645 December 11, 2018 Bell et al.
10153653 December 11, 2018 Bell et al.
10153660 December 11, 2018 Leabman et al.
10158257 December 18, 2018 Leabman
10158259 December 18, 2018 Leabman
10164478 December 25, 2018 Leabman
10170917 January 1, 2019 Bell et al.
10177594 January 8, 2019 Contopanagos
10181756 January 15, 2019 Bae et al.
10186892 January 22, 2019 Hosseini et al.
10186893 January 22, 2019 Bell et al.
10186911 January 22, 2019 Leabman
10186913 January 22, 2019 Leabman et al.
10193396 January 29, 2019 Bell et al.
10199835 February 5, 2019 Bell
10199849 February 5, 2019 Bell
10199850 February 5, 2019 Leabman
10205239 February 12, 2019 Contopanagos et al.
10206185 February 12, 2019 Leabman et al.
10211674 February 19, 2019 Leabman et al.
10211680 February 19, 2019 Leabman et al.
10211682 February 19, 2019 Bell et al.
10211685 February 19, 2019 Bell et al.
10218207 February 26, 2019 Hosseini et al.
10218227 February 26, 2019 Leabman et al.
10223717 March 5, 2019 Bell
10224758 March 5, 2019 Leabman et al.
10224982 March 5, 2019 Leabman
10230266 March 12, 2019 Leabman et al.
10243414 March 26, 2019 Leabman et al.
10256657 April 9, 2019 Hosseini et al.
10256677 April 9, 2019 Hosseini et al.
10263432 April 16, 2019 Leabman et al.
10263476 April 16, 2019 Leabman
10270261 April 23, 2019 Bell et al.
10277054 April 30, 2019 Hosseini
10291055 May 14, 2019 Bell et al.
10291056 May 14, 2019 Bell et al.
10291066 May 14, 2019 Leabman
10291294 May 14, 2019 Leabman
10298024 May 21, 2019 Leabman
10298133 May 21, 2019 Leabman
10305315 May 28, 2019 Leabman et al.
10312715 June 4, 2019 Leabman
10320446 June 11, 2019 Hosseini
10333332 June 25, 2019 Hosseini
10355534 July 16, 2019 Johnston et al.
10381880 August 13, 2019 Leabman et al.
10389161 August 20, 2019 Hosseini et al.
10396588 August 27, 2019 Leabman
10396604 August 27, 2019 Bell et al.
10439442 October 8, 2019 Hosseini et al.
10439448 October 8, 2019 Bell et al.
10447093 October 15, 2019 Hosseini
10476312 November 12, 2019 Johnston et al.
10483768 November 19, 2019 Bell et al.
10490346 November 26, 2019 Contopanagos
10491029 November 26, 2019 Hosseini
10498144 December 3, 2019 Leabman et al.
10511097 December 17, 2019 Komaros et al.
10511196 December 17, 2019 Hosseini
10516289 December 24, 2019 Leabman et al.
10516301 December 24, 2019 Leabman
10523033 December 31, 2019 Leabman
10523058 December 31, 2019 Leabman
10554052 February 4, 2020 Bell et al.
10594165 March 17, 2020 Hosseini
10615647 April 7, 2020 Johnston et al.
10680319 June 9, 2020 Hosseini et al.
10714984 July 14, 2020 Hosseini et al.
10734717 August 4, 2020 Hosseini
10778041 September 15, 2020 Leabman
10790674 September 29, 2020 Bell et al.
10840743 November 17, 2020 Johnston et al.
10879740 December 29, 2020 Hosseini
10923954 February 16, 2021 Leabman
10958095 March 23, 2021 Leabman et al.
10985617 April 20, 2021 Johnston et al.
11011942 May 18, 2021 Liu
20020065052 May 30, 2002 Pande et al.
20020103447 August 1, 2002 Terry
20020171594 November 21, 2002 Fang
20030038750 February 27, 2003 Chen
20030058187 March 27, 2003 Billiet et al.
20040020100 February 5, 2004 O'Brian et al.
20040130425 July 8, 2004 Dayan et al.
20040130442 July 8, 2004 Breed
20040145342 July 29, 2004 Lyon
20040155832 August 12, 2004 Yuanzhu
20040207559 October 21, 2004 Milosavljevic
20040259604 December 23, 2004 Mickle et al.
20050007276 January 13, 2005 Barrick et al.
20050116683 June 2, 2005 Cheng
20050117660 June 2, 2005 Vialle et al.
20050134517 June 23, 2005 Gottl
20050227619 October 13, 2005 Lee et al.
20050237258 October 27, 2005 Abramov et al.
20060013335 January 19, 2006 Leabman
20060019712 January 26, 2006 Choi
20060030279 February 9, 2006 Leabman et al.
20060092079 May 4, 2006 de Rochemont
20060094425 May 4, 2006 Mickle et al.
20060113955 June 1, 2006 Nunally
20060119532 June 8, 2006 Yun et al.
20060160517 July 20, 2006 Yoon
20060199620 September 7, 2006 Greene et al.
20060238365 October 26, 2006 Vecchione et al.
20060266564 November 30, 2006 Perlman et al.
20060266917 November 30, 2006 Baldis et al.
20060284593 December 21, 2006 Nagy et al.
20070007821 January 11, 2007 Rossetti
20070019693 January 25, 2007 Graham
20070021140 January 25, 2007 Keyes
20070060185 March 15, 2007 Simon et al.
20070090997 April 26, 2007 Brown et al.
20070093269 April 26, 2007 Leabman et al.
20070097653 May 3, 2007 Gilliland et al.
20070103110 May 10, 2007 Sagoo
20070106894 May 10, 2007 Zhang
20070109121 May 17, 2007 Cohen
20070139000 June 21, 2007 Kozuma
20070149162 June 28, 2007 Greene et al.
20070164868 July 19, 2007 Deavours et al.
20070173214 July 26, 2007 Mickle et al.
20070178857 August 2, 2007 Greene et al.
20070178945 August 2, 2007 Cook et al.
20070182367 August 9, 2007 Partovi
20070191074 August 16, 2007 Harrist et al.
20070191075 August 16, 2007 Greene et al.
20070210960 September 13, 2007 Rofougaran et al.
20070222681 September 27, 2007 Greene et al.
20070228833 October 4, 2007 Stevens et al.
20070229261 October 4, 2007 Zimmerman et al.
20070240297 October 18, 2007 Yang et al.
20070273486 November 29, 2007 Shiotsu
20070296639 December 27, 2007 Hook et al.
20070298846 December 27, 2007 Greene et al.
20080014897 January 17, 2008 Cook et al.
20080024376 January 31, 2008 Norris et al.
20080048917 February 28, 2008 Achour et al.
20080067874 March 20, 2008 Tseng
20080074324 March 27, 2008 Puzella et al.
20080089277 April 17, 2008 Alexander et al.
20080110263 May 15, 2008 Klessel et al.
20080122297 May 29, 2008 Arai
20080123383 May 29, 2008 Shionoiri
20080169910 July 17, 2008 Greene et al.
20080197802 August 21, 2008 Onishi
20080204350 August 28, 2008 Tam et al.
20080210762 September 4, 2008 Osada et al.
20080211458 September 4, 2008 Lawther et al.
20080233890 September 25, 2008 Baker
20080258993 October 23, 2008 Gummalla et al.
20080266191 October 30, 2008 Hilgers
20080278378 November 13, 2008 Chang et al.
20080309452 December 18, 2008 Zeine
20090002493 January 1, 2009 Kates
20090010316 January 8, 2009 Rofougaran et al.
20090019183 January 15, 2009 Wu et al.
20090036065 February 5, 2009 Siu
20090039828 February 12, 2009 Jakubowski
20090047998 February 19, 2009 Alberth, Jr.
20090058361 March 5, 2009 John
20090058731 March 5, 2009 Geary et al.
20090060012 March 5, 2009 Gresset et al.
20090067198 March 12, 2009 Graham et al.
20090067208 March 12, 2009 Martin et al.
20090073066 March 19, 2009 Jordon et al.
20090096412 April 16, 2009 Huang
20090096413 April 16, 2009 Partovi
20090102292 April 23, 2009 Cook et al.
20090102296 April 23, 2009 Greene et al.
20090108679 April 30, 2009 Porwal
20090122847 May 14, 2009 Nysen et al.
20090128262 May 21, 2009 Lee et al.
20090174604 July 9, 2009 Keskitalo
20090200985 August 13, 2009 Zane et al.
20090206791 August 20, 2009 Jung
20090207092 August 20, 2009 Nysen et al.
20090218884 September 3, 2009 Soar
20090218891 September 3, 2009 McCollough
20090243397 October 1, 2009 Cook et al.
20090256752 October 15, 2009 Akkermans et al.
20090264069 October 22, 2009 Yamasuge
20090271048 October 29, 2009 Wakamatsu
20090281678 November 12, 2009 Wakamatsu
20090284082 November 19, 2009 Mohammadian
20090284220 November 19, 2009 Toncich et al.
20090284227 November 19, 2009 Mohammadian et al.
20090286475 November 19, 2009 Toncich et al.
20090286476 November 19, 2009 Toncich et al.
20090291634 November 26, 2009 Saarisalo
20090312046 December 17, 2009 Clevenger et al.
20090322281 December 31, 2009 Kamijo et al.
20100001683 January 7, 2010 Huang et al.
20100007307 January 14, 2010 Baarman et al.
20100007569 January 14, 2010 Sim et al.
20100019908 January 28, 2010 Cho et al.
20100033021 February 11, 2010 Bennett
20100034238 February 11, 2010 Bennett
20100044123 February 25, 2010 Perlman et al.
20100060534 March 11, 2010 Oodachi
20100066631 March 18, 2010 Puzella et al.
20100075607 March 25, 2010 Hosoya
20100079005 April 1, 2010 Hyde et al.
20100079011 April 1, 2010 Hyde et al.
20100087227 April 8, 2010 Francos et al.
20100090656 April 15, 2010 Shearer et al.
20100109443 May 6, 2010 Cook et al.
20100117926 May 13, 2010 DeJean, II
20100123618 May 20, 2010 Martin et al.
20100123624 May 20, 2010 Minear et al.
20100127660 May 27, 2010 Cook et al.
20100142418 June 10, 2010 Nishioka et al.
20100142509 June 10, 2010 Zhu et al.
20100148723 June 17, 2010 Cook et al.
20100151808 June 17, 2010 Toncich et al.
20100156741 June 24, 2010 Vazquez et al.
20100164296 July 1, 2010 Kurs et al.
20100164433 July 1, 2010 Janefalker et al.
20100167664 July 1, 2010 Szini
20100171461 July 8, 2010 Baarman et al.
20100171676 July 8, 2010 Tani et al.
20100174629 July 8, 2010 Taylor et al.
20100176934 July 15, 2010 Chou et al.
20100181961 July 22, 2010 Novak et al.
20100181964 July 22, 2010 Huggins et al.
20100194206 August 5, 2010 Burdo et al.
20100201189 August 12, 2010 Kirby et al.
20100201201 August 12, 2010 Mobarhan et al.
20100201314 August 12, 2010 Toncich et al.
20100207572 August 19, 2010 Kirby et al.
20100210233 August 19, 2010 Cook et al.
20100213895 August 26, 2010 Keating et al.
20100214177 August 26, 2010 Parsche
20100222010 September 2, 2010 Ozaki et al.
20100225270 September 9, 2010 Jacobs et al.
20100227570 September 9, 2010 Hendin
20100244576 September 30, 2010 Hillan et al.
20100253281 October 7, 2010 Li
20100256831 October 7, 2010 Abramo et al.
20100259447 October 14, 2010 Crouch
20100264747 October 21, 2010 Hall et al.
20100277003 November 4, 2010 Von Novak et al.
20100279606 November 4, 2010 Hillan et al.
20100289341 November 18, 2010 Ozaki
20100295372 November 25, 2010 Hyde et al.
20100309088 December 9, 2010 Hyvonen et al.
20100315045 December 16, 2010 Zeine
20100328044 December 30, 2010 Waffenschmidt et al.
20110009057 January 13, 2011 Saunamäki
20110013198 January 20, 2011 Shirley
20110018360 January 27, 2011 Baarman et al.
20110028114 February 3, 2011 Kerselaers
20110032149 February 10, 2011 Leabman
20110032866 February 10, 2011 Leabman
20110034190 February 10, 2011 Leabman
20110034191 February 10, 2011 Leabman
20110043047 February 24, 2011 Karalis et al.
20110043163 February 24, 2011 Baarman et al.
20110043327 February 24, 2011 Baarman et al.
20110050166 March 3, 2011 Cook et al.
20110053500 March 3, 2011 Menegoli
20110057607 March 10, 2011 Carobolante
20110057853 March 10, 2011 Kim et al.
20110062788 March 17, 2011 Chen et al.
20110074342 March 31, 2011 MacLaughlin
20110074349 March 31, 2011 Ghovanloo
20110109167 May 12, 2011 Park et al.
20110115303 May 19, 2011 Baarman et al.
20110115432 May 19, 2011 El-Maleh
20110115605 May 19, 2011 Dimig et al.
20110121660 May 26, 2011 Azancot et al.
20110122018 May 26, 2011 Tarng et al.
20110122026 May 26, 2011 DeLaquil et al.
20110127845 June 2, 2011 Walley et al.
20110127952 June 2, 2011 Walley et al.
20110133691 June 9, 2011 Hautanen
20110151789 June 23, 2011 Viglione et al.
20110154429 June 23, 2011 Stantchev
20110156493 June 30, 2011 Bennett
20110156494 June 30, 2011 Mashinsky
20110156640 June 30, 2011 Moshfeghi
20110175455 July 21, 2011 Hashiguchi
20110175461 July 21, 2011 Tinaphong
20110181120 July 28, 2011 Liu et al.
20110182245 July 28, 2011 Malkamaki et al.
20110184842 July 28, 2011 Melen
20110194543 August 11, 2011 Zhao et al.
20110195722 August 11, 2011 Walter et al.
20110199046 August 18, 2011 Tsai et al.
20110215086 September 8, 2011 Yeh
20110217923 September 8, 2011 Ma
20110220634 September 15, 2011 Yeh
20110221389 September 15, 2011 Won et al.
20110222272 September 15, 2011 Yeh
20110227725 September 22, 2011 Muirhead
20110243040 October 6, 2011 Khan et al.
20110243050 October 6, 2011 Yanover
20110244913 October 6, 2011 Kim et al.
20110248573 October 13, 2011 Kanno et al.
20110248575 October 13, 2011 Kim et al.
20110249678 October 13, 2011 Bonicatto
20110254377 October 20, 2011 Widmer et al.
20110254503 October 20, 2011 Widmer et al.
20110259953 October 27, 2011 Baarman et al.
20110273977 November 10, 2011 Shapira et al.
20110278941 November 17, 2011 Krishna et al.
20110279226 November 17, 2011 Chen et al.
20110281535 November 17, 2011 Low et al.
20110282415 November 17, 2011 Eckhoff et al.
20110285213 November 24, 2011 Kowalewski
20110286374 November 24, 2011 Shin et al.
20110291489 December 1, 2011 Tsai et al.
20110302078 December 8, 2011 Failing
20110304216 December 15, 2011 Baarman
20110304437 December 15, 2011 Beeler
20110304521 December 15, 2011 Ando et al.
20120007441 January 12, 2012 John
20120013196 January 19, 2012 Kim et al.
20120013198 January 19, 2012 Uramoto et al.
20120013296 January 19, 2012 Heydari et al.
20120019419 January 26, 2012 Prat et al.
20120025622 February 2, 2012 Kim et al.
20120043887 February 23, 2012 Mesibov
20120051109 March 1, 2012 Kim et al.
20120051294 March 1, 2012 Guillouard
20120056486 March 8, 2012 Endo et al.
20120056741 March 8, 2012 Zhu et al.
20120068906 March 22, 2012 Asher et al.
20120074891 March 29, 2012 Anderson et al.
20120075072 March 29, 2012 Pappu
20120080944 April 5, 2012 Recker et al.
20120080957 April 5, 2012 Cooper et al.
20120086284 April 12, 2012 Capanella et al.
20120086615 April 12, 2012 Norair
20120095617 April 19, 2012 Martin et al.
20120098350 April 26, 2012 Campanella et al.
20120098485 April 26, 2012 Kang et al.
20120099675 April 26, 2012 Kitamura et al.
20120103562 May 3, 2012 Clayton
20120104849 May 3, 2012 Jackson
20120105252 May 3, 2012 Wang
20120112532 May 10, 2012 Kesler et al.
20120119914 May 17, 2012 Uchida
20120126743 May 24, 2012 Rivers, Jr.
20120132647 May 31, 2012 Beverly et al.
20120133214 May 31, 2012 Yun et al.
20120142291 June 7, 2012 Rath et al.
20120146426 June 14, 2012 Sabo
20120146576 June 14, 2012 Partovi
20120146577 June 14, 2012 Tanabe
20120147802 June 14, 2012 Ukita et al.
20120149307 June 14, 2012 Terada et al.
20120150670 June 14, 2012 Taylor et al.
20120153894 June 21, 2012 Widmer et al.
20120157019 June 21, 2012 Li
20120161531 June 28, 2012 Kim et al.
20120161544 June 28, 2012 Kashiwagi et al.
20120169276 July 5, 2012 Wang
20120169278 July 5, 2012 Choi
20120173418 July 5, 2012 Beardsmore et al.
20120179004 July 12, 2012 Roesicke et al.
20120181973 July 19, 2012 Lyden
20120182427 July 19, 2012 Marshall
20120188142 July 26, 2012 Shashi et al.
20120187851 July 26, 2012 Huggins et al.
20120193999 August 2, 2012 Zeine
20120200399 August 9, 2012 Chae
20120201153 August 9, 2012 Bharadia et al.
20120201173 August 9, 2012 Jian et al.
20120206299 August 16, 2012 Valdes-Garcia
20120211214 August 23, 2012 Phan
20120212071 August 23, 2012 Miyabayashi et al.
20120212072 August 23, 2012 Miyabayashi et al.
20120214462 August 23, 2012 Chu et al.
20120214536 August 23, 2012 Kim et al.
20120228392 September 13, 2012 Cameron et al.
20120228956 September 13, 2012 Kamata
20120231856 September 13, 2012 Lee et al.
20120235636 September 20, 2012 Partovi
20120242283 September 27, 2012 Kim et al.
20120248886 October 4, 2012 Kesler et al.
20120248888 October 4, 2012 Kesler et al.
20120248891 October 4, 2012 Drennen
20120249051 October 4, 2012 Son et al.
20120262002 October 18, 2012 Widmer et al.
20120265272 October 18, 2012 Judkins
20120267900 October 25, 2012 Huffman et al.
20120268238 October 25, 2012 Park et al.
20120270592 October 25, 2012 Ngai
20120274154 November 1, 2012 DeLuca
20120280650 November 8, 2012 Kim et al.
20120286582 November 15, 2012 Kim et al.
20120292993 November 22, 2012 Mettler et al.
20120293021 November 22, 2012 Teggatz et al.
20120293119 November 22, 2012 Park et al.
20120294054 November 22, 2012 Kim et al.
20120299389 November 29, 2012 Lee et al.
20120299540 November 29, 2012 Perry
20120299541 November 29, 2012 Perry
20120299542 November 29, 2012 Perry
20120300588 November 29, 2012 Perry
20120300592 November 29, 2012 Perry
20120300593 November 29, 2012 Perry
20120306284 December 6, 2012 Lee et al.
20120306433 December 6, 2012 Kim et al.
20120306572 December 6, 2012 Hietala et al.
20120306705 December 6, 2012 Sakurai et al.
20120306707 December 6, 2012 Yang et al.
20120306720 December 6, 2012 Tanmi et al.
20120307873 December 6, 2012 Kim et al.
20120309295 December 6, 2012 Maguire
20120309308 December 6, 2012 Kim et al.
20120309332 December 6, 2012 Liao
20120313446 December 13, 2012 Park et al.
20120313449 December 13, 2012 Kurs
20120313835 December 13, 2012 Gebretnsae
20120326660 December 27, 2012 Lu et al.
20130002550 January 3, 2013 Zalewski
20130005252 January 3, 2013 Lee et al.
20130018439 January 17, 2013 Chow et al.
20130024059 January 24, 2013 Miller et al.
20130026981 January 31, 2013 Van Der Lee
20130026982 January 31, 2013 Rothenbaum
20130032589 February 7, 2013 Chung
20130033571 February 7, 2013 Steen
20130038124 February 14, 2013 Newdoll et al.
20130038402 February 14, 2013 Karalis et al.
20130043738 February 21, 2013 Park et al.
20130044035 February 21, 2013 Zhuang
20130049471 February 28, 2013 Oleynik
20130049475 February 28, 2013 Kim et al.
20130049484 February 28, 2013 Weissentern et al.
20130057078 March 7, 2013 Lee
20130057205 March 7, 2013 Lee et al.
20130057210 March 7, 2013 Negaard et al.
20130057364 March 7, 2013 Kesler et al.
20130058379 March 7, 2013 Kim et al.
20130062959 March 14, 2013 Lee et al.
20130063082 March 14, 2013 Lee et al.
20130063143 March 14, 2013 Adalsteinsson et al.
20130063266 March 14, 2013 Yunker et al.
20130069444 March 21, 2013 Waffenschmidt et al.
20130076308 March 28, 2013 Niskala et al.
20130077650 March 28, 2013 Traxler et al.
20130078918 March 28, 2013 Crowley et al.
20130082651 April 4, 2013 Park et al.
20130082653 April 4, 2013 Lee et al.
20130083774 April 4, 2013 Son et al.
20130088082 April 11, 2013 Kang et al.
20130088090 April 11, 2013 Wu
20130088192 April 11, 2013 Eaton
20130088331 April 11, 2013 Cho
20130093388 April 18, 2013 Partovi
20130099389 April 25, 2013 Hong et al.
20130099586 April 25, 2013 Kato
20130106197 May 2, 2013 Bae et al.
20130107023 May 2, 2013 Tanaka et al.
20130119777 May 16, 2013 Rees
20130119778 May 16, 2013 Jung
20130119929 May 16, 2013 Partovi
20130120052 May 16, 2013 Siska
20130120205 May 16, 2013 Thomson et al.
20130120206 May 16, 2013 Biancotto et al.
20130120217 May 16, 2013 Ueda et al.
20130130621 May 23, 2013 Kim et al.
20130132010 May 23, 2013 Winger et al.
20130134923 May 30, 2013 Smith
20130137455 May 30, 2013 Xia
20130141037 June 6, 2013 Jenwatanavet et al.
20130148341 June 13, 2013 Williams
20130149975 June 13, 2013 Yu et al.
20130154387 June 20, 2013 Lee et al.
20130155748 June 20, 2013 Sundstrom
20130157729 June 20, 2013 Tabe
20130162335 June 27, 2013 Kim et al.
20130169061 July 4, 2013 Microshnichenko et al.
20130169219 July 4, 2013 Gray
20130169348 July 4, 2013 Shi
20130171939 July 4, 2013 Tian et al.
20130175877 July 11, 2013 Abe et al.
20130178253 July 11, 2013 Karaoguz
20130181881 July 18, 2013 Christie et al.
20130187475 July 25, 2013 Vendik
20130190031 July 25, 2013 Persson et al.
20130193769 August 1, 2013 Mehta et al.
20130197320 August 1, 2013 Albert et al.
20130200064 August 8, 2013 Alexander
20130207477 August 15, 2013 Nam et al.
20130207604 August 15, 2013 Zeine
20130207879 August 15, 2013 Rada et al.
20130210357 August 15, 2013 Qin et al.
20130221757 August 29, 2013 Cho et al.
20130222201 August 29, 2013 Ma et al.
20130234530 September 12, 2013 Miyauchi
20130234536 September 12, 2013 Chemishkian et al.
20130234658 September 12, 2013 Endo et al.
20130241306 September 19, 2013 Aber et al.
20130241468 September 19, 2013 Moshfeghi
20130241474 September 19, 2013 Moshfeghi
20130249478 September 26, 2013 Hirano
20130249479 September 26, 2013 Partovi
20130249682 September 26, 2013 Van Wiemeersch et al.
20130250102 September 26, 2013 Scanlon et al.
20130253612 September 26, 2013 Chow
20130254578 September 26, 2013 Huang et al.
20130264997 October 10, 2013 Lee et al.
20130268782 October 10, 2013 Tam et al.
20130270923 October 17, 2013 Cook et al.
20130278076 October 24, 2013 Proud
20130278209 October 24, 2013 Von Novak
20130285464 October 31, 2013 Miwa
20130285477 October 31, 2013 Lo et al.
20130285606 October 31, 2013 Ben-Shalom et al.
20130288600 October 31, 2013 Kuusilinna et al.
20130288617 October 31, 2013 Kim et al.
20130293423 November 7, 2013 Moshfeghi
20130300356 November 14, 2013 Yang
20130307751 November 21, 2013 Yu-Juin et al.
20130310020 November 21, 2013 Kazuhiro
20130311798 November 21, 2013 Sultenfuss
20130328417 December 12, 2013 Takeuchi
20130334883 December 19, 2013 Kim et al.
20130339108 December 19, 2013 Ryder et al.
20130343208 December 26, 2013 Sexton et al.
20130343251 December 26, 2013 Zhang
20130343585 December 26, 2013 Bennett et al.
20140001846 January 2, 2014 Mosebrook
20140001875 January 2, 2014 Nahidipour
20140001876 January 2, 2014 Fujiwara et al.
20140006017 January 2, 2014 Sen
20140008993 January 9, 2014 Leabman
20140009110 January 9, 2014 Lee
20140011531 January 9, 2014 Burstrom et al.
20140015336 January 16, 2014 Weber et al.
20140015344 January 16, 2014 Mohamadi
20140021907 January 23, 2014 Yu et al.
20140021908 January 23, 2014 McCool
20140035524 February 6, 2014 Zeine
20140035526 February 6, 2014 Tripathi et al.
20140035786 February 6, 2014 Ley
20140043248 February 13, 2014 Yeh
20140049422 February 20, 2014 Von Novak et al.
20140054971 February 27, 2014 Kissin
20140055098 February 27, 2014 Lee et al.
20140057618 February 27, 2014 Zirwas et al.
20140062395 March 6, 2014 Kwon et al.
20140063666 March 6, 2014 Kallal
20140082435 March 20, 2014 Kitgawa
20140086125 March 27, 2014 Polo et al.
20140086592 March 27, 2014 Nakahara et al.
20140091756 April 3, 2014 Ofstein et al.
20140091968 April 3, 2014 Harel et al.
20140091974 April 3, 2014 Desclos et al.
20140103869 April 17, 2014 Radovic
20140104157 April 17, 2014 Burns
20140111147 April 24, 2014 Soar
20140111153 April 24, 2014 Kwon et al.
20140113689 April 24, 2014 Lee
20140117946 May 1, 2014 Muller et al.
20140118140 May 1, 2014 Amis
20140128107 May 8, 2014 An
20140132210 May 15, 2014 Partovi
20140133279 May 15, 2014 Khuri-Yakub
20140139034 May 22, 2014 Sankar et al.
20140139039 May 22, 2014 Cook et al.
20140139180 May 22, 2014 Kim et al.
20140141838 May 22, 2014 Cai et al.
20140142876 May 22, 2014 John et al.
20140143933 May 29, 2014 Low et al.
20140145879 May 29, 2014 Pan
20140145884 May 29, 2014 Dang et al.
20140152117 June 5, 2014 Sanker
20140159651 June 12, 2014 Von Novak et al.
20140159652 June 12, 2014 Hall et al.
20140159662 June 12, 2014 Furui
20140159667 June 12, 2014 Kim et al.
20140169385 June 19, 2014 Hadani et al.
20140175893 June 26, 2014 Sengupta et al.
20140176054 June 26, 2014 Porat et al.
20140176061 June 26, 2014 Cheatham, III et al.
20140176082 June 26, 2014 Visser
20140177399 June 26, 2014 Teng et al.
20140183964 July 3, 2014 Walley
20140184148 July 3, 2014 Van Der Lee et al.
20140184155 July 3, 2014 Cha
20140184163 July 3, 2014 Das et al.
20140184170 July 3, 2014 Jeong
20140191568 July 10, 2014 Partovi
20140191818 July 10, 2014 Waffenschmidt et al.
20140194092 July 10, 2014 Wanstedt et al.
20140194095 July 10, 2014 Wanstedt et al.
20140197691 July 17, 2014 Wang
20140203629 July 24, 2014 Hoffman et al.
20140206384 July 24, 2014 Kim et al.
20140210281 July 31, 2014 Ito et al.
20140217955 August 7, 2014 Lin
20140217967 August 7, 2014 Zeine et al.
20140225805 August 14, 2014 Pan et al.
20140232320 August 21, 2014 Ento July et al.
20140232610 August 21, 2014 Shigemoto et al.
20140239733 August 28, 2014 Mach et al.
20140241231 August 28, 2014 Zeine
20140245036 August 28, 2014 Oishi
20140246416 September 4, 2014 White
20140247152 September 4, 2014 Proud
20140252813 September 11, 2014 Lee et al.
20140252866 September 11, 2014 Walsh et al.
20140265725 September 18, 2014 Angle et al.
20140265727 September 18, 2014 Berte
20140265943 September 18, 2014 Angle et al.
20140266025 September 18, 2014 Jakubowski
20140266946 September 18, 2014 Bily et al.
20140273819 September 18, 2014 Nadakuduti et al.
20140273892 September 18, 2014 Nourbakhsh
20140281655 September 18, 2014 Angle et al.
20140292090 October 2, 2014 Cordeiro et al.
20140292451 October 2, 2014 Zimmerman
20140300452 October 9, 2014 Rofe et al.
20140312706 October 23, 2014 Fiorello et al.
20140325218 October 30, 2014 Shimizu et al.
20140327320 November 6, 2014 Muhs et al.
20140327390 November 6, 2014 Park et al.
20140333142 November 13, 2014 Desrosiers
20140346860 November 27, 2014 Aubry et al.
20140354063 December 4, 2014 Leabman et al.
20140354221 December 4, 2014 Leabman et al.
20140355718 December 4, 2014 Guan et al.
20140368048 December 18, 2014 Leabman et al.
20140368161 December 18, 2014 Leabman et al.
20140368405 December 18, 2014 Ek et al.
20140375139 December 25, 2014 Tsukamoto
20140375253 December 25, 2014 Leabman et al.
20140375258 December 25, 2014 Arkhipenkov
20140375261 December 25, 2014 Manova-Elssibony et al.
20150001949 January 1, 2015 Leabman et al.
20150002086 January 1, 2015 Matos et al.
20150003207 January 1, 2015 Lee et al.
20150008980 January 8, 2015 Kim et al.
20150011160 January 8, 2015 Uurgovan et al.
20150015180 January 15, 2015 Miller et al.
20150015182 January 15, 2015 Brandtman et al.
20150015192 January 15, 2015 Leabman et al.
20150021990 January 22, 2015 Myer et al.
20150022008 January 22, 2015 Leabman et al.
20150022010 January 22, 2015 Leabman et al.
20150022194 January 22, 2015 Almalki et al.
20150023204 January 22, 2015 Wil et al.
20150028688 January 29, 2015 Masaoka
20150028694 January 29, 2015 Leabman et al.
20150028697 January 29, 2015 Leabman et al.
20150028875 January 29, 2015 Irie et al.
20150035378 February 5, 2015 Calhoun et al.
20150035709 February 5, 2015 Lim
20150035715 February 5, 2015 Kim et al.
20150039482 February 5, 2015 Fuinaga
20150041459 February 12, 2015 Leabman et al.
20150042265 February 12, 2015 Leabman et al.
20150044977 February 12, 2015 Ramasamy et al.
20150046526 February 12, 2015 Bush et al.
20150061404 March 5, 2015 Lamenza et al.
20150076917 March 19, 2015 Leabman et al.
20150076927 March 19, 2015 Leabman et al.
20150077036 March 19, 2015 Leabman et al.
20150077037 March 19, 2015 Leabman et al.
20150091520 April 2, 2015 Blum et al.
20150091706 April 2, 2015 Chemishkian et al.
20150097442 April 9, 2015 Muurinen
20150097663 April 9, 2015 Sloo et al.
20150102764 April 16, 2015 Leabman et al.
20150102769 April 16, 2015 Leabman et al.
20150102942 April 16, 2015 Houser et al.
20150102973 April 16, 2015 Hand et al.
20150108848 April 23, 2015 Joehren
20150109181 April 23, 2015 Hyde et al.
20150115877 April 30, 2015 Aria et al.
20150115878 April 30, 2015 Park
20150116153 April 30, 2015 Chen et al.
20150128733 May 14, 2015 Taylor et al.
20150130285 May 14, 2015 Leabman et al.
20150130293 May 14, 2015 Hajimiri et al.
20150137612 May 21, 2015 Yamakawa et al.
20150145350 May 28, 2015 Hajimiri
20150148664 May 28, 2015 Stolka et al.
20150155737 June 4, 2015 Mayo
20150155738 June 4, 2015 Leabman et al.
20150162662 June 11, 2015 Chen et al.
20150162751 June 11, 2015 Leabman et al.
20150162779 June 11, 2015 Lee et al.
20150171512 June 18, 2015 Chen et al.
20150171513 June 18, 2015 Chen et al.
20150171656 June 18, 2015 Leabman et al.
20150171658 June 18, 2015 Manova-Elssibony et al.
20150171931 June 18, 2015 Won et al.
20150177326 June 25, 2015 Chakraborty et al.
20150180133 June 25, 2015 Hunt
20150180249 June 25, 2015 Jeon et al.
20150180284 June 25, 2015 Kang et al.
20150181117 June 25, 2015 Park et al.
20150187491 July 2, 2015 Yanagawa
20150188352 July 2, 2015 Peek et al.
20150199665 July 16, 2015 Chu
20150201385 July 16, 2015 Mercer et al.
20150207333 July 23, 2015 Baarman et al.
20150207542 July 23, 2015 Zeine
20150222126 August 6, 2015 Leabman et al.
20150233987 August 20, 2015 Von Novak, III et al.
20150234144 August 20, 2015 Cameron et al.
20150236520 August 20, 2015 Baarman
20150236877 August 20, 2015 Peng et al.
20150244070 August 27, 2015 Cheng et al.
20150244080 August 27, 2015 Gregoire
20150244187 August 27, 2015 Horie
20150244201 August 27, 2015 Chu
20150244341 August 27, 2015 Ritter et al.
20150249484 September 3, 2015 Mach et al.
20150255989 September 10, 2015 Walley et al.
20150256097 September 10, 2015 Gudan et al.
20150260835 September 17, 2015 Widmer et al.
20150262465 September 17, 2015 Pritchett
20150263534 September 17, 2015 Lee et al.
20150263548 September 17, 2015 Cooper
20150270618 September 24, 2015 Zhu et al.
20150270622 September 24, 2015 Takasaki et al.
20150270741 September 24, 2015 Leabman et al.
20150278558 October 1, 2015 Priev et al.
20150280429 October 1, 2015 Makita et al.
20150280484 October 1, 2015 Radziemski et al.
20150288074 October 8, 2015 Harper et al.
20150288438 October 8, 2015 Maltsev et al.
20150311585 October 29, 2015 Church et al.
20150312721 October 29, 2015 Singh
20150318729 November 5, 2015 Leabman
20150326024 November 12, 2015 Bell et al.
20150326070 November 12, 2015 Petras et al.
20150326072 November 12, 2015 Petras et al.
20150326143 November 12, 2015 Petras et al.
20150327085 November 12, 2015 Hadani
20150333528 November 19, 2015 Leabman
20150333573 November 19, 2015 Leabman
20150333800 November 19, 2015 Perry et al.
20150339497 November 26, 2015 Kurian
20150340759 November 26, 2015 Bridgelall et al.
20150340903 November 26, 2015 Bell et al.
20150341087 November 26, 2015 Moore et al.
20150358222 December 10, 2015 Berger et al.
20150365137 December 17, 2015 Miller et al.
20150365138 December 17, 2015 Miller et al.
20160005068 January 7, 2016 Im et al.
20160012695 January 14, 2016 Bell et al.
20160013560 January 14, 2016 Daniels
20160013661 January 14, 2016 Kurs et al.
20160013677 January 14, 2016 Bell et al.
20160013855 January 14, 2016 Campos
20160020636 January 21, 2016 Khlat
20160028403 January 28, 2016 McCaughan et al.
20160033254 February 4, 2016 Zeine et al.
20160042206 February 11, 2016 Pesavento et al.
20160043562 February 11, 2016 Lisi et al.
20160043571 February 11, 2016 Kesler et al.
20160043572 February 11, 2016 Cooper et al.
20160054440 February 25, 2016 Younis
20160056635 February 25, 2016 Bell
20160056640 February 25, 2016 Mao
20160065005 March 3, 2016 Won et al.
20160079799 March 17, 2016 Khlat
20160087483 March 24, 2016 Hietala et al.
20160087486 March 24, 2016 Pogorelik et al.
20160094091 March 31, 2016 Shin et al.
20160094092 March 31, 2016 Davlantes et al.
20160099601 April 7, 2016 Leabman et al.
20160099611 April 7, 2016 Leabman et al.
20160099612 April 7, 2016 Leabman et al.
20160099614 April 7, 2016 Leabman et al.
20160099755 April 7, 2016 Leabman et al.
20160099757 April 7, 2016 Leabman et al.
20160112787 April 21, 2016 Rich
20160126749 May 5, 2016 Shichino et al.
20160126752 May 5, 2016 Vuori et al.
20160126776 May 5, 2016 Kim et al.
20160141908 May 19, 2016 Jakl et al.
20160164563 June 9, 2016 Khawand et al.
20160174162 June 16, 2016 Nadakuduti et al.
20160181849 June 23, 2016 Govindaraj
20160181867 June 23, 2016 Daniel et al.
20160181873 June 23, 2016 Mitcheson et al.
20160197522 July 7, 2016 Zeine et al.
20160202343 July 14, 2016 Okutsu
20160204642 July 14, 2016 Oh
20160218545 July 28, 2016 Schroeder et al.
20160233582 August 11, 2016 Piskun
20160238365 August 18, 2016 Wixey et al.
20160240908 August 18, 2016 Strong
20160248276 August 25, 2016 Hong et al.
20160294225 October 6, 2016 Blum et al.
20160299210 October 13, 2016 Zeine
20160301240 October 13, 2016 Zeine
20160322868 November 3, 2016 Akuzawa et al.
20160323000 November 3, 2016 Liu et al.
20160336804 November 17, 2016 Son et al.
20160339258 November 24, 2016 Perryman et al.
20160344098 November 24, 2016 Ming
20160359367 December 8, 2016 Rothschild
20160380464 December 29, 2016 Chin et al.
20160380466 December 29, 2016 Yang et al.
20170005481 January 5, 2017 Von Novak, III
20170005516 January 5, 2017 Leabman et al.
20170005524 January 5, 2017 Akuzawa et al.
20170005530 January 5, 2017 Zeine et al.
20170012448 January 12, 2017 Miller et al.
20170025887 January 26, 2017 Hyun et al.
20170025903 January 26, 2017 Song et al.
20170026087 January 26, 2017 Tanabe
20170040700 February 9, 2017 Leung
20170043675 February 16, 2017 Jones et al.
20170047784 February 16, 2017 Jung et al.
20170063168 March 2, 2017 Uchida
20170077733 March 16, 2017 Jeong et al.
20170077765 March 16, 2017 Bell et al.
20170077979 March 16, 2017 Papa et al.
20170077995 March 16, 2017 Leabman
20170085120 March 23, 2017 Leabman et al.
20170085437 March 23, 2017 Condeixa et al.
20170092115 March 30, 2017 Sloo et al.
20170110886 April 20, 2017 Reynolds et al.
20170110910 April 20, 2017 Zeine et al.
20170127196 May 4, 2017 Blum et al.
20170134686 May 11, 2017 Leabman
20170141582 May 18, 2017 Adolf et al.
20170141583 May 18, 2017 Adolf et al.
20170163076 June 8, 2017 Park et al.
20170168595 June 15, 2017 Sakaguchi et al.
20170179763 June 22, 2017 Leabman
20170214422 July 27, 2017 Na et al.
20170274787 September 28, 2017 Salter et al.
20170338695 November 23, 2017 Port
20180006611 January 4, 2018 de Jong et al.
20180040929 February 8, 2018 Chappelle
20180048178 February 15, 2018 Leabman
20180090992 March 29, 2018 Shrivastava et al.
20180102675 April 12, 2018 Wheeland
20180212523 July 26, 2018 Leabman
20180226840 August 9, 2018 Leabman
20180241255 August 23, 2018 Leabman
20180262050 September 13, 2018 Yankowitz
20180301934 October 18, 2018 Prabhala et al.
20180309314 October 25, 2018 White, II
20180343040 November 29, 2018 Luzinski et al.
20180375368 December 27, 2018 Leabman et al.
20180376235 December 27, 2018 Leabman
20190052979 February 14, 2019 Chen et al.
20190074728 March 7, 2019 Leabman
20190074862 March 7, 2019 Wang et al.
20190131827 May 2, 2019 Johnston
20190180157 June 13, 2019 Yase
20190245389 August 8, 2019 Johnston
20190288567 September 19, 2019 Leabman et al.
20190296586 September 26, 2019 Moshfeghi
20190326782 October 24, 2019 Graham et al.
20190372384 December 5, 2019 Hosseini et al.
20190386522 December 19, 2019 Park et al.
20190393729 December 26, 2019 Contopanagos et al.
20190393928 December 26, 2019 Leabman
20200006988 January 2, 2020 Leabman
20200021128 January 16, 2020 Bell et al.
20200091608 March 19, 2020 Alpman et al.
20200112204 April 9, 2020 Hosseini et al.
20200153117 May 14, 2020 Papio-Toda et al.
20200203837 June 25, 2020 Komaros et al.
20200235614 July 23, 2020 Swan et al.
20200244104 July 30, 2020 Katajamaki et al.
20200244111 July 30, 2020 Johnston et al.
20200252141 August 6, 2020 Sarajedini
20200274397 August 27, 2020 Hwang et al.
20200313642 October 1, 2020 Mimino
20210091602 March 25, 2021 Woo
Foreign Patent Documents
201278367 July 2009 CN
102227884 October 2011 CN
102292896 December 2011 CN
102860037 January 2013 CN
103151848 June 2013 CN
103348563 October 2013 CN
203826555 September 2014 CN
104090265 October 2014 CN
104167773 November 2014 CN
104347915 February 2015 CN
105765821 July 2016 CN
106329116 January 2017 CN
103380561 September 2017 CN
20016655 February 2002 DE
102013216953 February 2015 DE
1028482 August 2000 EP
1081506 March 2001 EP
2346136 July 2011 EP
2397973 February 2012 EP
2545635 January 2013 EP
2747195 June 2014 EP
3067983 September 2016 EP
3118970 January 2017 EP
3145052 March 2017 EP
2404497 February 2005 GB
2556620 June 2018 GB
2000323916 November 2000 JP
2002319816 October 2002 JP
2006157586 June 2006 JP
2007043432 February 2007 JP
2008167017 July 2008 JP
2009525715 July 2009 JP
2009201328 September 2009 JP
2012016171 January 2012 JP
2012095226 May 2012 JP
2012157167 August 2012 JP
2013099249 May 2013 JP
2013162624 August 2013 JP
2014075927 April 2014 JP
2014112063 June 2014 JP
2014176131 September 2014 JP
2015027345 February 2015 JP
2015128349 July 2015 JP
2015128370 July 2015 JP
WO2015177859 April 2017 JP
20060061776 June 2006 KR
20070044302 April 2007 KR
100755144 September 2007 KR
20110132059 February 2011 KR
20110135540 December 2011 KR
20120009843 February 2012 KR
20120108759 October 2012 KR
20130026977 March 2013 KR
20140023409 February 2014 KR
20140023410 March 2014 KR
20140085200 July 2014 KR
20150077678 July 2015 KR
20170050971 May 2017 KR
2658332 June 2018 RU
WO 199508125 March 1995 WO
WO 199831070 July 1998 WO
WO 199952173 October 1999 WO
WO 2000111716 February 2001 WO
WO 2003091943 November 2003 WO
WO 2004077550 September 2004 WO
WO 2006122783 November 2006 WO
WO 2007070571 June 2007 WO
WO 2008024993 February 2008 WO
WO 2008156571 December 2008 WO
WO 2010022181 February 2010 WO
WO 2010039246 April 2010 WO
WO 2010138994 December 2010 WO
WO 2011112022 September 2011 WO
WO 2012177283 December 2012 WO
WO 2013031988 March 2013 WO
WO 2013035190 March 2013 WO
WO 2013038074 March 2013 WO
WO 2013042399 March 2013 WO
WO 2013052950 April 2013 WO
WO 2013105920 July 2013 WO
WO 2013175596 November 2013 WO
WO 2014068992 May 2014 WO
WO 2014075103 May 2014 WO
WO 2014113093 July 2014 WO
WO 2014132258 September 2014 WO
WO 2014134996 September 2014 WO
WO 2014182788 November 2014 WO
WO 2014182788 November 2014 WO
WO 2014197472 December 2014 WO
WO 2014209587 December 2014 WO
WO 2015038773 March 2015 WO
WO 2015097809 July 2015 WO
WO 2015130902 September 2015 WO
WO 2015161323 October 2015 WO
WO 2016024869 February 2016 WO
WO 2016048512 March 2016 WO
WO 2016088261 June 2016 WO
WO 2016187357 November 2016 WO
Other references
  • Energous Corp., IPRP, PCT/US2014/040697, Dec. 8, 2015, 9 pgs.
  • Energous Corp., IPRP, PCT/US2014/040705, Dec. 8, 2015, 6 pgs.
  • Energous Corp., IPRP, PCT/US2014/045119, Jan. 12, 2016, 9 pgs.
  • Energous Corp., IPRP, PCT/US2014/048002, Feb. 12, 2015, 8 pgs.
  • Energous Corp., IPRP, PCT/US2014/049669, Feb. 9, 2016, 8 pgs.
  • Energous Corp., IPRP, PCT/US2014/059317, Apr. 12, 2016, 10 pgs.
  • Energous Corp., IPRP, PCT/US2014/059340, Apr. 12, 2016, 11 pgs.
  • Energous Corp., IPRP, PCT/US2014/059871, Apr. 12, 2016, 9 pgs.
  • Energous Corp., IPRP, PCT/US2014/062661, May 3, 2016, 10 pgs.
  • Energous Corp., IPRP, PCT/US2014/068282, Jun. 7, 2016, 10 pgs.
  • Energous Corp., IPRP, PCT/US2014/068586, Jun. 14, 2016, 8 pgs.
  • Energous Corp., IPRP, PCT/US2015/067242, Jun. 27, 2017, 7 pgs.
  • Energous Corp., IPRP, PCT/US2015/067243, Jun. 27, 2017, 7 pgs.
  • Energous Corp., IPRP, PCT/US2015/067245, Jun. 27, 2017, 7 pgs.
  • Energous Corp., IPRP, PCT/US2015/067246, Jun. 27, 2017, 9 pgs.
  • Energous Corp., IPRP, PCT/US2015/067249, Jun. 27, 2017, 7 pgs.
  • Energous Corp., IPRP, PCT/US2015/067250, Mar. 30, 2016, 10 pgs.
  • Energous Corp., IPRP, PCT/US2015/067271, Jul. 4, 2017, 5 pgs.
  • Energous Corp., IPRP, PCT/US2015/067275, Jul. 4, 2017, 7 pgs.
  • Energous Corp., IPRP, PCT/US2015/067279, Jul. 4, 2017, 7 pgs.
  • Energous Corp., IPRP, PCT/US2015/067282, Jul. 4, 2017, 6 pgs.
  • Energous Corp., IPRP, PCT/US2015/067287, Jul. 4, 2017, 6 pgs.
  • Energous Corp., IPRP, PCT/US2015/067291, Jul. 4, 2017, 4 pgs.
  • Energous Corp., IPRP, PCT/US2015/067294, Jul. 4, 2017, 6 pgs.
  • Energous Corp., IPRP, PCT/US2015/067325, Jul. 4, 2017, 8 pgs.
  • Energous Corp., IPRP, PCT/US2015/067334, Jul. 4, 2017, 5 pgs.
  • Energous Corp., IPRP, PCT/US2016/068495, Jun. 26, 2018, 7 pgs.
  • Energous Corp., IPRP, PCT/US2016/068551, Jun. 26, 2018, 6 pgs.
  • Energous Corp., IPRP, PCT/US2016/068987, Jul. 3, 2018, 7 pgs.
  • Energous Corp., IPRP, PCT/US2016/068993, Jul. 3, 2018, 10 pgs.
  • Energous Corp., IPRP, PCT/US2017/046800, Feb. 12, 2019, 10 pgs.
  • Energous Corp., IPRP, PCT/US2017/065886, Jun. 18, 2019, 10 pgs.
  • Energous Corp., IPRP, PCT/US2018/012806, Jul. 9, 2019, 6 pgs.
  • Energous Corp., IPRP, PCT/US2018/025465, Oct. 1, 2019, 8 pgs.
  • Energous Corp., IPRP, PCT/US2018/031768, Nov. 12, 2019, 8 pgs.
  • Energous Corp., IPRP, PCT/US2018/031786, Apr. 14, 2020, 7 pgs.
  • Energous Corp., IPRP, PCT/US2018/039334, Dec. 24, 2019, 8 pgs.
  • Energous Corp., IPRP, PCT/US2018/051082, Mar. 17, 2020, 9 pgs.
  • Energous Corp., IPRP, PCT/US2018/058178, May 5, 2020, 7 pgs.
  • Energous Corp., IPRP, PCT/US2019/015 820, Aug. 4, 2020, 7 pgs.
  • Energous Corp., IPRP, PCT/US2019/021817, Sep. 15, 2020, 7 pgs.
  • Energous Corp., ISRWO, PCT/US2014/037072, Sep. 12, 2014, 8 pgs.
  • Energous Corp., ISRWO, PCT/US2014/037109, Apr. 8, 2016, 12 pgs.
  • Energous Corp., ISRWO, PCT/US2014/037170, Sep. 15, 2014, 11 pgs.
  • Energous Corp., ISRWO, PCT/US2014/040648, Oct. 10, 2014, 11 pgs.
  • Energous Corp., ISRWO, PCT/US2014/040697, Oct. 1, 2014, 12 pgs.
  • Energous Corp., ISRWO, PCT/US2014/040705, Sep. 23, 2014, 8 pgs.
  • Energous Corp., ISRWO, PCT/US2014/041323, Oct. 1, 2014, 10 pgs.
  • Energous Corp., ISRWO, PCT/US2014/041342, Jan. 27, 2015, 10 pgs.
  • Energous Corp., ISRWO, PCT/US2014/041534, Oct. 13, 2014, 10 pgs.
  • Energous Corp., ISRWO, PCT/US2014/041546, Oct. 16, 2014, 12 pgs.
  • Energous Corp., ISRWO, PCT/US2014/041558, Oct. 10, 2014, 8 pgs.
  • Energous Corp., ISRWO, PCT/US2014/044810 Oct. 21, 2014, 12 pgs.
  • Energous Corp., ISRWO, PCT/US2014/045102, Oct. 28, 2014, 14 pgs.
  • Energous Corp., ISRWO, PCT/US2014/045119, Oct. 13, 2014, 11 pgs.
  • Energous Corp., ISRWO, PCT/US2014/045237, Oct. 13, 2014, 16 pgs.
  • Energous Corp., ISRWO, PCT/US2014/046941, Nov. 6, 2014, 11 pgs.
  • Energous Corp., ISRWO, PCT/US2014/046956, Nov. 12, 2014, 10 pgs.
  • Energous Corp., ISRWO, PCT/US2014/046961, Nov. 24, 2014, 16 pgs.
  • Energous Corp., ISRWO, PCT/US2014/047963, Nov. 7, 2014, 13 pgs.
  • Energous Corp., ISRWO, PCT/US2014/048002, Nov. 13, 2014, 11 pgs.
  • Energous Corp., ISRWO, PCT/US2014/049666, Nov. 10, 2014, 7 pgs.
  • Energous Corp., ISRWO, PCT/US2014/049669, Nov. 13, 2014, 10 pgs.
  • Energous Corp., ISRWO, PCT/US2014/049673, Nov. 18, 2014, 10 pgs.
  • Energous Corp., ISRWO, PCT/US2014/054891, Dec. 18, 2014, 12 pgs.
  • Energous Corp., ISRWO, PCT/US2014/054897, Feb. 17, 2015, 10 pgs.
  • Energous Corp., ISRWO, PCT/US2014/054953, Dec. 4, 2014, 7 pgs.
  • Energous Corp., ISRWO, PCT/US2014/055195, Dec. 22, 2014, 11 pgs.
  • Energous Corp., ISRWO, PCT/US2014/059317, Feb. 24, 2015, 13 pgs.
  • Energous Corp., ISRWO, PCT/US2014/059340, Jan. 15, 2015, 13 pgs.
  • Energous Corp., ISRWO, PCT/US2014/059871, Jan. 23, 2015, 12 pgs.
  • Energous Corp., ISRWO, PCT/US2014/062661, Jan. 27, 2015, 12 pgs.
  • Energous Corp., ISRWO, PCT/US2014/062672, Jan. 26, 2015, 11 pgs.
  • Energous Corp., ISRWO, PCT/US2014/062682, Feb. 12, 2015, 10 pgs.
  • Energous Corp., ISRWO, PCT/US2014/068282, Mar. 19, 2015, 13 pgs.
  • Energous Corp., ISRWO, PCT/US2014/068568, Mar. 20, 2015, 10 pgs.
  • Energous Corp., ISRWO, PCT/US2014/068586, Mar. 20, 2015, 11 pgs.
  • Energous Corp., ISRWO, PCT/US2015/067242, Mar. 16, 2016, 9 pgs.
  • Energous Corp., ISRWO, PCT/US2015/067243, Mar. 10, 2016, 11 pgs.
  • Energous Corp., ISRWO, PCT/US2015/067245, Mar. 17, 2016, 8 pgs.
  • Energous Corp., ISRWO, PCT/US2015/067246, May 11, 2016, 18 pgs.
  • Energous Corp., ISRWO, PCT/US2015/067249, Mar. 29, 2016, 8 pgs.
  • Energous Corp., ISRWO, PCT/US2015/067250, Mar. 30, 2016, 11 pgs.
  • Energous Corp., ISRWO, PCT/US2015/067271, Mar. 11, 2016, 6 pgs.
  • Energous Corp., ISRWO, PCT/US2015/067275, Mar. 3, 2016, 8 pgs.
  • Energous Corp., ISRWO, PCT/US2015/067279, Mar. 11, 2015, 13 pgs.
  • Energous Corp., ISRWO, PCT/US2015/067282, Jul. 5, 2016, 7 pgs.
  • Energous Corp., ISRWO, PCT/US2015/067287, Feb. 2, 2016, 8 pgs.
  • Energous Corp., ISRWO, PCT/US2015/067291, Mar. 4, 2016, 10 pgs.
  • Energous Corp., ISRWO, PCT/US2015/067294, Mar. 29, 2016, 7 pgs.
  • Energous Corp., ISRWO, PCT/US2015/067325, Mar. 10, 2016, 9 pgs.
  • Energous Corp., ISRWO, PCT/US2015/067334, Mar. 3, 2016, 6 pgs.
  • Energous Corp., ISRWO, PCT/US2016/068495, Mar. 30, 2017, 9 pgs.
  • Energous Corp., ISRWO, PCT/US2016/068498, May 17, 2017, 8 pgs.
  • Energous Corp., ISRWO, PCT/US2016/068504, Mar. 30, 2017, 8 pgs.
  • Energous Corp., ISRWO, PCT/US2016/068551, Mar. 17, 2017, 8 pgs.
  • Energous Corp., ISRWO, PCT/US2016/068565, Mar. 8, 2017, 11 pgs.
  • Energous Corp., ISRWO, PCT/US2016/068987, May 8, 2017, 10 pgs.
  • Energous Corp., ISRWO, PCT/US2016/068993, Mar. 13, 2017, 12 pgs.
  • Energous Corp., ISRWO, PCT/US2016/069313, Nov. 13, 2017, 10 pgs.
  • Energous Corp., ISRWO, PCT/US2016/069316, Mar. 16, 2017, 15 pgs.
  • Energous Corp., ISRWO, PCT/US2017/046800, Sep. 11, 2017, 13 pgs.
  • Energous Corp., ISRWO, PCT/US2017/065886, Apr. 6, 2018, 13 pgs.
  • Energous Corp., ISRWO, PCT/US2018/012806, Mar. 23, 2018, 9 pgs.
  • Energous Corp., ISRWO, PCT/US2018/025465, Jun. 22, 2018, 9 pgs.
  • Energous Corp., ISRWO, PCT/US2018/031768, Jul. 3, 2018, 9 pgs.
  • Energous Corp., ISRWO, PCT/US2018/031786, Aug. 8, 2018, 9 pgs.
  • Energous Corp., ISRWO, PCT/US2018/039334, Sep. 11, 2018, 9 pgs.
  • Energous Corp., ISRWO, PCT/US2018/051082, Dec. 12, 2018, 9 pgs.
  • Energous Corp., ISRWO, PCT/US2018/058178, Mar. 13, 2019, 10 pgs.
  • Energous Corp., ISRWO, PCT/US2018/064289, Apr. 25, 2019, 12 pgs.
  • Energous Corp., ISRWO, PCT/US2019/015 820, May 14, 2019, 9 pgs.
  • Energous Corp., ISRWO, PCT/US2019/021817, Apr. 6, 2019, 11 pgs.
  • Energous Corp., ISRWO, PCT/US2019/039014, Oct. 4, 2019, 15 pgs.
  • Energous Corp., ISRWO, PCT/US2019/061445, Jan. 7, 2020, 19 pgs.
  • Energous Corp., ISRWO, PCT/US2020/051693, Jan. 7, 2021, 18 pgs.
  • Order Granting Reexamination Request, U.S. Appl. No. 90/013,793 dated Aug. 31, 2016, 23 pgs.
  • Notice of Intent to Issue Reexam Certificate: U.S. Appl. No. 90/013,793 dated Feb. 2, 2017, 8 pgs.
  • Ossia Inc. vs Energous Corp., Declaration of Stephen B. Heppe in Support of Petition for Post-Grant Review of U.S. Pat. No. 9,124,125, PGR2016-00023, May 31, 2016, 144 pgs.
  • Ossia Inc. vs Energous Corp., Declaration of Stephen B. Heppe in Support of Petition for Post-Grant Review of U.S. Pat. No. 9,124,125, PGR2016-00024, May 31, 2016, 122 pgs.
  • Ossia Inc. vs Energous Corp., Patent Owner Preliminary Response, Sep. 8, 2016, 95 pgs.
  • Ossia Inc. vs Energous Corp., Petition for Post Grant Review of U.S. Pat. No. 9,124,125, May 31, 2016, 86 pgs.
  • Ossia Inc. vs Energous Corp., Petition for Post-Grant Review of U.S. Pat. No. 9,124,125, May 31, 2016, 92 pgs.
  • Ossia Inc. vs Energous Corp., PGR2016-00023-Institution Decision, Nov. 29, 2016, 29 pgs.
  • Ossia Inc. vs Energous Corp., PGR2016-00024-Institution Decision, Nov. 29, 2016, 50 pgs.
  • Ossia Inc. vs Energous Corp., PGR2016-00024-Judgement-Adverse, Jan. 20, 2017, 3 pgs.
  • Adamiuk et al. “Compact, Dual-Polarized UWB-Antanna, Embedded in a Dielectric,” IEEE Transactions on Antenna and Propagation, IEEE Service Center, Piscataway, NJ, US vol. 56, No. 2, Feb. 1, 2010, 8 pgs.
  • Gill et al. “A System for Change Detection and Human Recognition in Voxel Space using the Microsoft Kinect Sensor,” 2011 IEEE Applied Imagery Pattern Recognition Workshop. 8 pgs.
  • Han et al. Enhanced Computer Vision with Microsoft Kinect Sensor: A Review, IEEE Transactions on Cybernetics vol. 43, No. 5, pp. 1318-1334, Oct. 3, 2013.
  • Hsieh et al. “Development of a Retrodirective Wireless Microwave Power Transmission System”, IEEE, 2003 pp. 393-396.
  • Leabman “Adaptive Band-partitioning for Interference Cancellation in Communication System,” Thesis Massachusetts Institute of Technology, Feb. 1997, pp. 1-70.
  • Li et al. High-Efficiency Switching-Mode Charger System Design Considerations with Dynamic Power Path Management, Mar./Apr. 2012 Issue, 8 pgs.
  • Mao et al. “BeamStar: An Edge-Based Approach to Routing in Wireless Sensors Networks”, IEEE Transactions on Mobile Computing, IEEE Service Center, Los Alamitos, CA US, vol. 6, No. 11, Nov. 1, 2007, 13 pgs.
  • Mascarenas et al. “Experimental Studies of Using Wireless Energy Transmission for Powering Embedded Sensor Nodes,” Nov. 28, 2009, Journal of Sound and Vibration, 13 pgs.
  • Mishra et al. “SIW-based Slot Array Antenna and Power Management Circuit for Wireless Energy Harvesting Applications”, IEEE APSURSI, Jul. 2012, 2 pgs.
  • Nenzi et al. “U-Helix: On-Chip Short Conical Antenna”, 2013 7th European Conference on Antennas and Propagation (EUCAP), ISBN:978-1-4673-2187-7, IEEE, Apr. 8, 2013, 5 pgs.
  • Qing et al. “UHF Near-Field Segmented Loop Antennas with Enlarged Interrogation Zone,” 2012 IEEE International Workshop on Antenna Technology (iWAT), Mar. 1, 2012, pp. 132-135, XP055572059, ISBN: 978-1-4673-0035-3.
  • Singh “Wireless Power Transfer Using Metamaterial Bonded Microstrip Antenna for Smart Grid WSN”, Fourth International Conference on Advances in Computing and Communications (ICACC), Aug. 27-29, 2014, Abstract 1 pg.
  • Smolders “Broadband Microstrip Array Antennas” Institute of Electrical 1-15 and Electronics Engineers, Digest of the Antennas and Propagation Society International Symposium. Seattle, WA, Jun. 19-24, 1994, Abstract 3 pgs.
  • Van Veen et al., “Beamforming: A Versatile Approach to Spatial Filtering”, IEEE, ASSP Magazine, Apr. 1988, pp. 4-24.
  • Wei et al. “Design of a Wideband Horizontally Polarized Omnidirectional Printed Loop Antenna,” IEEE Antennas and Wireless Propagation Letters, vol. 11, Jan. 3, 2012, 4 pgs.
  • Zeng et al. “A Compact Fractal Loop Rectenna for RF Energy Harvesting,” IEEE Antennas and Wireless Propagation Letters, vol. 16, Jun. 26, 2017, 4 pgs.
  • Zhai et al. “A Practical Wireless Charging System Based on Ultra-Wideband Retro-Reflective Beamforming” 2010 IEEE Antennas and Propagation Society International Symposium, Toronto, ON 2010, 4 pgs.
Patent History
Patent number: 11411441
Type: Grant
Filed: Sep 19, 2020
Date of Patent: Aug 9, 2022
Patent Publication Number: 20210091602
Assignee: ENERGOUS CORPORATION (San Jose, CA)
Inventor: Wayne Eumchan Woo (San Jose, CA)
Primary Examiner: Rexford N Barnie
Assistant Examiner: David A Shiao
Application Number: 17/026,198
Classifications
Current U.S. Class: Electromagnet Or Highly Inductive Systems (307/104)
International Classification: H02J 50/27 (20160101); H02J 50/23 (20160101);